Page 1 :
Points to Remember, 1. Organism (Microorganism, plant and animals) who posseses life is living., 2. Life is a complex organisation expressing itself through chemical reactions, and exhibit characteristics of living organisms., 3. Characteristics of Living Organisms : Growth, reproduction, metabolism,, cellular organisation, consciousness (ability to sense environment), selfreplicating and self regulation.,  Reproduction and growth are NOT defining properties.,  Metabolism, cellular organisation and consciousness are defining, properties.,  Living organisms are self-replicating, evolving, self-regulating and, interactive systems capable of responding to external stimuli., 4. Biodiversity : Term used to refer to the variety of microorganisms, plant, and animals on earth., 5. Need for classification : To organise the vast number of microorganisms,, plants and animals into categories that could be named, remembered, studied, and understood., 6. Three Domains of Life : Proposed by Carl Woese in 1990 who also proposed, the six kingdom classification for living organisms. The three Domains of, life are Archaea, Bacteria and Eukarya., 1, Kingdom, Archaea → 1. Archaebacteria, 2, Domains, Bacteria → 2. Eutacteria, of life, 3, Eukarya → 3. Protista, → 4. Fungi, → 5. Plantae, → 6. Animalia, , www.cleariitmedical.com

Page 2 :
7. Taxonomy : Study of principles and procedures of identification, nomenclature, and classification., 8. Systematics : It deals with classification of organisms based on their, diversities and relationships among them. Term was proposed by Carolus, Linnaeus who wrote ‘Systema Naturae’., 9. Concept of Species : All the members that can interbreed among themselves, and can produce fertile offsprings are the members of same species. This is, the biological concept of species proposed by Mayr., 10. Taxa : Each category (i.e., unit) of classification is called as a taxon., 11. Taxonomic Hierarchy : Classification of organisms in a defnite sequence, of taxon or category or rank in a desending order., Kingdom → Phylum /Division → Class → Order → Family → Genus → Species., , 12. Binomial Nomenclature : Given by Carolus Linnaeus. Each scientific name, has two components-Generic name + Specific epithet., 13. ICBN : International Code for Botanical Nomenclature (for giving scientific, name to plants.), 14. ICZN : International Code of Zoological Nomenclature (for giving scientific, name to animals.), 15. Rule for Nomenclature :, , Latinised names are used., , First word is genus, second word is species name., , Printed in italics; if handwritten then underlined separately., , First word starts with capital letter while species name written in small, letter., 16.  Scientific names of some organisms :, Man, —, Homo sapiens, Housefly, —, Musca domestica, Mango, —, Mangifera indica, Wheat, —, Triticum aestivum, 17. Taxonomical Aids are the tools for study of taxonomy., 18. Museums in educational institutes (school and colleges) have collection of, skeletons of animals, stuffed and preserved specimens of organisms for study, and reference., 19. Zoological Parks (Places where wild animals are kept in protected environment, under human care) Example : National Zoological Park, Delhi., 20. Herbarium : Store house of dried, pressed and preserved plant specimen, on sheets, kept systematically according to a widely accepted system of, classification, for future use., , www.cleariitmedical.com

Page 3 :
21. Botanical Garden : Collection of living plants for reference., Example : Royal Batanical garden Kew (England), National Botanical, Research Institute (Lucknow), Indian Botanical Garden Howrah., 22. Keys : (Used for indentification of plants and animals on the basis of similarities, and dissimilarities.), 23. Couplet : are the two alternate characteristic statement used in key to identify, organisation., 24. Each Statement of the key is called a lead., 25., , , , 26., , , , 27., , , , Flora (Index to plant species found in a particular area., Manuals (Provide information for identification of name of species in an, area.), Mongoraphs (Contain information on any one taxon.), , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 5 :
, , Halophiles (salt-loving), , , , Thermoacidophiles (in hot springs), , , , , , , , , , , , , , Methanogens (in marsh and in gut of ruminant animals. Produce methane, gas.), Photosynthetic autotrophs like Cyanobacteria (Blue-green algae BGA)., Some like Anabaena and Nostoc have specialized cells called heterocysts, for nitrogen ixation., Algae bloom is rich growth of blue green algae over the surface of polluted, water bodies., Algae bloom releases neurotoxins, deplete oxygen and makes water unit, for use., Chemosynthetic autotrophs : Oxidise various inorganic substances like, nitrates/nitrites, ammonia and use released energy for their ATP proudction., They helps in nutrients recycling of N, P, Fe and S., Heterotophic bacteria : Decomposers help in making curd, production of, antibiotic, N2 ixation, casuse disesaes like cholera, typhoid, tetanus and, citrus canker., Mycoplasmas : Completely lack cell wall. Smallest living cells. Can survive, without oxygen. Pathogenic in animals and plants., , Kingdom PROTISTA, (Comprises of all single celled eukaryotes), , , Forms a link between plants, animals and fungi., (i), , Chrysophytes (Has diatoms and golden algae/desmids), Fresh water/marine, photosynthetic, microscopic plankton., , , , , Chief producers in Ocean., Cell walls have silica which makes it indestructible and cell walls, overlap to it together like a soap box., , , , Their accumulation forms ‘Diatomaceous Earth” (gritty soil), , , , Used in polishing, iltration of oils and syrups., , www.cleariitmedical.com

Page 6 :
(ii) Dinolagellates :, , , , , , , Marine, photosynthetic, cell wall has stiff cellulose plates., Two lagella–one longitudinal and other transverse in a furrow, between wall plates., Example : Gonyaulax multiples rapdily, make sea appear red (red, tides) and produce toxins to kill marine animals., , (iii) Euglenoids :, , , Found in stagnant fresh water., Have protein rich layer ‘pellicle’ which makes body lexible., , , , , , Photosynthetic in presence of sunlight but become heterotrophs if, they do not get sunlight. (Mixotrophic nutrition), Example : Euglena, , (iv) Slime Moulds :, , , , , , , , , Saprophytic protists, Under suitable conditions form an aggregates called plasmodium,, grows on decaying twigs and leaves., During unfavourable conditions, plasmodium differentiates and, forms fruiting bodies bearing spores at their tips., Spores have true walls which are extremely resistant and survive for, many years and dispersed by air currents., , (v) Protozoans : Are heterotrops and live as parasites. Have four major, groups., Amoeboid : Catch prey using pseudopodia, e.g., Amoeba. Entamoeba, are parasite., Flagellated : Have one or more lagella. Cause disease like Sleeping, Sickness e.g., trypanosoma., Ciliated : Have clilia to move food into gullet and help in locomotion., e.g., Paramoecium., Sporozoans : Have infective spore like stage in life cycle, e.g.,, Plasmodium which causes malaria., , www.cleariitmedical.com

Page 9 :
, , , , , , , , , , , Non-cellular organisms which take over the machinery of host cell on entering, it and become living but as such they have inert crystalline structure appear, non-living. So, dificult to call them living or non-living., Virus means venom or poisonous luid. Pastuer gave the term ‘virus’., D.J. Ivanowsky found out that certain microbes caused Tobacco Mosaic, Disease in tobacco plant., M.W. Beijerinek called luid as ‘Contagium vivum luidum’ as extracts of, infected plants of tobacco could cause infection in healthy plants., W.M. Stanely showed viruses could be crystallized to form crystals of protein, which are inert outside their speciic host., Viruses are obligate parasites., , Structure of Virus :, , , , , It is a nucleoprotein made up of protein coat called Capsid. Capsid is made, up of capsomeres arranged in helical or polyhedral-geometric forms. Have, either DNA or RNA as genetic material which may be single or double, stranded., Usually plant viruses have single stranded RNA; bacteriophages have double, stranded DNA and animal viruses have single or double stranded RNA or, double stranded DNA., , Diseases caused in humans :, Mumps, Small pox, herpes, inluenza and AIDS etc. In plants, symptoms can, be mosaic formation, leaf rolling and curling, yellowing and vein clearing,, dwaring and stunted growth., , Viroids :, , , Infectious agent, free RNA (lack protein coat), , , , RNA has low molecular weight., , , , Causes potato spindle tuber disease., , , , Discovered by T.O. Diener., , Lichens :, , , , , Symbiotic association between algal component (Phycobiont) and fungal, component (mycobiont). Algae provides food. Fungi provides shelter and, absorb nutrients and water for alga., Good pollution indicators as they do not grow in polluted areas., 25, , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 10 :
Points to Remember, Classification :, , , Artiicial System of Classiication, , , , , , , By Carolus Linnaeus, based on androecium structure and vegetative, characters., , Natural System of Classiication, , , Based on natural afinities among organisms, , , , Included external as well as internal features, , , , By Geroge Bentham and J.D. Hooker, , Phylogenetic System of Classication, , , Based on evolutionary relationships between the various organisms, , , , By Engler and Prantl, , , , Later on By Hutchinson, , Numerical Taxonomy :, , , Carried out using computers, , , , Based on all observable characteristics, , , , Data processed after assigning number and codes to all the characters., Advantages : Each character gets equal importance and a number of, characters can be considered., , Cytotaxonomy :, , , Based on cytological informations., , , , Gives importance to chromosome number, structure and behaviour., , www.cleariitmedical.com

Page 11 :
Chemotaxonomy :, , , Based on Chemical constitutents of the plants., , Algae :, , , Chlorophyll bearing, simple, thalloid, autotrophic and largely aquatic, organisms., , Importance of Algae :, , , Help in carbon dioxide ixation by carrying out photosynthesis and have, immense economic importance., , , , At least half of the total carbon dioxide ixation on earth carried out by them., , , , Increases dissolved oxygen level in their environment., , , , Many species like Laminaria, Sargassum, Porphyra etc. are used as food., , , , , , , , , , Agar obtained from Gelidium and Gracilaria which is used in ice-creams, and jellies and to grow microbes., Algin obtained from brown algae and carrageen from red algae used, commercially as hydrocolloids., Chlorella and Spirullina are unicellular algae, rich in protein and used even, by space travellers., Algae are unicellular like Chlamydomonas, colonial like Volvox or or, ilamentous like spirogyra and Ulothrix. Occur in water, soil, wood moist, stones etc., Algae are divided into 3 classes., , (i) Chlorophyceae, , , Green algae, Main pigment is chlorophyll ‘a’ and ‘b’., , , , Cell wall has inner layer of cellulose and outer layer of pectose., , , , Has pyrenoids made up of starch and proteins., , , , Pigment and pyrenoids are located in Chloroplast., e.g., Chlamydomonas, Volvax, Spirogyra, Ulothrix, Chara., , (ii) Phaeophyceae, , , Brown algae are brown coloured due to main pigments chlorophyll ‘a’,, , www.cleariitmedical.com

Page 13 :
Prevents soil erosion, alongwith lichens are irst colonizers on barren rock., , , Is divided into two classes Liverworts (thalloid body, dorsiventral, e.g.,, Marchantia) and Mosses (have two stages in gametophyte–creeping, green,, branched, ilamentous protonema stage and the leafy stage having spirally, arranged leaves e.g., Funaria, Polytrichum and Sphagnum)., , Reproduction in Bryophytes, , , Vegetative reproduction by fragmentation., , , , Asexual reproduction by gemmae formed in gemma cups., , , , Sexual reproduction : Main plant body is haploid, produces gametes and so, called Gametophyte. By fusion of antherozoids produced in antheridium, and egg cell produced in archegonium, results in formation of zygote which, develops into sporophytic structure differentiated into foot, seta and capsule., Spores produced in a capsule germinate to from free-living gametophyt e, (Protonema). Sporophyte is not free living but attached to photosynthetic, gametophyte from which derives nutrition., , Pteridophytes :, , , First terrestrial plants., , , , Prefer cool, damp and shady places to grow., , , , Grown as ornamentals., , , , Used for medicinal purpose, as soil binder., , , , , , , , , , , , Main plant body is sporophyte which is differentiated into true root, stem, and leaves., Leaves may be small as in Selaginella or large as in ferms., Sporangia having spores are subtended by leaf-like appendages called, sporophylls. (Sporphylls may be arranged to form strobili or cones.), In Sporangia, the spore mother cells give to spores after meiosis., Spores germinate to form haploid gametophytic structure called prothallus, which is free living, small, unicellular and photosynthetic., Prothallus bears antheridia and archegonia which bear antherozoids and, egg cell respectively which on fertilisation from zygote. Zygote produces, , www.cleariitmedical.com

Page 15 :
Angiosperms :, , , , , Called lowering plants and have seeds enclosed in fruits., Divided into two classes–Dicotyledons (have two cotyledons) and, Monocotyledons (have one cotyledon)., , , , Smallest angiosperm : Wolia, , , , Large tree : Eucalyptus (Over 100 meters), , , , , , , , , , , , Stamen has ilament and anther. Anthers bear pollen grains. Pollen grains, have two male gametes., Pistil has stigma, style and ovary. Ovary has ovule in which female gametophyt, e (embryo sac) develops., Embryo sac has 7 cells and 8 nuclei.One egg cell 2 synergids, 3 antipodals, and two polar nuclei which fuse to form secondary nucleus., Pollen grain is carried by wind, water, insects and other agents reaches to, stigma and produces pollen tube which enters embryo sac., Double fertilisation : One male gemate fuses with egg cell (Syngamy) to, form zygote which develops into embryo., , Other male gamete fuses with secondary nucleus (triple fusion) which forms, triploid primary endosperm nucleus (PEN). PEN develops into endosperm which, nourishes the developing embryo., , , Ovules develop into seeds and ovaries into fruits., , 34, , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 16 :
Point to Remember, Basis of Classification :, Animals are classiied on the basis of following few fundamental features—, 1. Levels of Organisation :, (1) Cellular level : Cells are arranged as loose cell aggregates, e.g.,sponges., (2) Tissue level : The cells performing the same function are arranged into, tissues, e.g., Coelenterates., (3) Organ level : Tissues are grouped together to form organs, each, specialised for a particular function. e.g., platyhelminthes., (4) Organ system level : organs are associated to form functional systems, e.g., Annelids, Arthropods, Molluscs, Echinoderms and Chordates., Example : Circulatory System., Open type : Blood pumped out through heart. Not conined to blood vessels., Cells and tissues are directly bathed in it., Closed types : Blood is circulated through blood vessels (arteries,veins and, capillaries), 2. Symmetry :,  Asymmetrical : Cannot be divided into equal halves through median plane, e.g., Sponges.,  Radial symmetry : Any plane passing through central axis can divide organism, into identical halves. e.g., coelentrates,Ctenophores and echinoderms.,  Bilateral symmetry : Only one plane can divide the organism into two identical, left and right halves e.g., Annelids and Arthropods., 3. Germinal Layers :, Diploblastic : Cells arranged in two embryonic layers i.e., external ectoderm, and internal endoderm. (Mesoglea may be present in between ectoderm and, endoderm) e.g., porifers and Coelentrates. (Cnidarians), Triploblastic : Three layers present in developing embryo i.e., ectoderm,, mesoderm and endoderm. e.g., Platyhelminthes to Chordates., , www.cleariitmedical.com

Page 17 :
4. Coelom (Body cavity which is lined by mesoderm), Coelomates : Have coelom e.g., Annelids, Arthropods, molluscs, Echinoderms,, Chordates etc., Pseudocoelomates : No true coelem as mesoderm is present in scattered, pouches between ectoderm and endoderm. e.,g., Aschelminthes., Acoelomates : Body cavity is absent e.g., Platyhelminthes., 5. Segmentation (A) True Metamerism : Found Annelida,Arthropoda,, Chordata :,  Segmentation is external as well as a internal in Annelids.,  Segmentation is external in Arthropods.,  Segmentation is internal in chordates.,  Metamerism : If body is externally and internally divided into segments, (metameres) with serial repetition of atleast some organs, then phenomenon is, called metamerism e.g., Earthworm. (B) Pseudometamerism : Found in, tapeworm. The proglottids (segments of tapeworm) budded off from neck, not embryonic in origin., 6. Notochord :,  Rod-like structure formed during embryonic development on t he dorsal side., It is mesodermally derived e.g., Chordates.,  Non-chordates do not have notochord .e.g., porifera to echinoderms., , Phylum Porifera :, , , , , , , , , , , Also called sponges., Are usually marine and asymmetrical., Have cellular level of organisation and diploblastic animals., Food gathering, respiratory exchange and removal of wastes occurs through, water canal system. Digestion intracellular., Ostia (minute pores on body), spongocoel (body cavity) and osculum help, in water transport. They are lined by choanocytes (collar cells)., Body wall has skeleton of spicules or spongin ibres., Animals are hermaphrodite. Fertilisation internal. Development is indirect, (i.e., has a larval stage distinct from adult stage) e.g., Sycon, Euspongia., Spongilla (Fresh water sponge), , Phylum Coelenterata :, , , , , Also called Cnidarians., Are usually marine and radially symmetrical., Sessile or free swimming., , www.cleariitmedical.com

Page 18 :
, , , , , , , , , , , , Have tissue level of organisation., Are diploblastic (with mesogloea), Capture of prey, anchorage and defence occurs through cnidoblasts/cnidocytes, (have stinging capsules nematocytes) present on tentacles., Digestion extracellular and intracellular., Have a central gastro-vascular cavity and an opening, hypostome., Body wall of some composed of calcium carbonate. e.g. corals., exhibit two body forms : polyp and medusa e.g., Hydra, Aurelia., Alternation of generation between body forms called metagenesis ocurs in, Obelia where :, Medusa, Polyp. (Sessile and cylindrical), (free swimming &, umbrella shaped), e.g., Physalia, Adamsia, Pennatula, Gorgonia,Meandrina., , Phylum Ctenophora :, , , Also called as sea walnuts or comb jellies., , , , Are exclusively marine, radially symmetrical., , , , Have tissue level organisation, are diploblastic., , , , Digestion both extra and intracellular., , , , Body has eight external rows of ciliated comb plates for locomotion., , , , Show Bioluminescence (Property of living organisms to emit light)., , , , Hermaphrodite (sexes are not separate)., , , , Only sexual reproduction occurs. Exernal fertilization. Indirect development., e.g., Ctenoplana, Pleurobrachia., , Phylum Plathyhelminthes :, , , , , , , , , Also called as ‘lat worms’., Have dorsoventrally lattened body. Are mostly endoparasites in animals., Are bilaterally symmetrical, triploblastic, acoelomate,with organ level of, orgnisation., Absorb nutrients through body surface., Parasitic forms have hooks and suckers., ‘Flame cells’ help in osmoregulation and excretion., , www.cleariitmedical.com

Page 19 :
, , , Sexes not separate., Fertilisation internal. Many larval stages present. Planaria has high, regeneration capacity. e.g., Taenia, Fasciola., , Phylum Aschelminthes :, , , , , , , , , , Also called ‘round worms’., May be free living, parasitic, aquatic or terrestrial., Are bilaterally symmetrical, triploblastic, pseudocoelomate., Alimentary canal complete (has muscular pharynx), wastes removed through, excretory pore., Sexes separate. (dioecious), Females longer than males., Fertilisation internal. Development direct or indirect. e.g., Ascaris,Wuchereria,, Ancylostoma., , Phyum Annelida :, , , , , , , , , , , , , , , Are aquatic or terrestrial, free-living or parasitic., Are bilaterally symmetrical, triploblastic, organ-system level of organisation, and metamerically segmented body., Are coelomate animals., Have longitudinal and circular muscles for locomation., Have closed circulatory system., Nereis (dioecious and aquatic annelid) has lateral appendages called parapodia, for swimming., Have nephridia for osmoregulation and excretion., Neural system consists of paired gangila connected by lateral nerves to a, double ventral nerve cord., Reproduction is sexual., e.g., Earthworm (Pheretima) and Leech (Hirudinaria) which are hermaph, rodites (i.e., monoecious)., , Phylum Arthropoda :, , , , , , Largest phylum of Animalia., Are bilaterally symmetrical, triplobastic, segmented externally and organ, system level of organisation, coelomate., Body divisible into head, thorax, abdomen and has a chitinous exoskeleton., Jointed appendages are present., , 40, , www.cleariitmedical.com

Page 20 :
, , , , , Respiration by gills, book gills, book lungs or tracheal system. Excretion, through malpighian tubules., Sensory organs : Antennae, eyes; Organs of balance : Statocysts., Fertilisation usaully internal. Development is indirect or direct. Are mostly, oviparous., e.g., Apis, Bombyx, Laccifer, Anopheles, Culex, Aedes, Locusta, Limulus., , Phulum Mollusca :, , , , , , , , , , , , , Second largest phylum of Animalia., Terrestrial or aquatic, Are bilaterally symmetrical, triplobastic and organ system level of organisation,, coelomate., Body vidisble into head, muscular foot and visceral hump and is covered, by calcareous shell and is unsegmented., Mantle : Soft and spongy layer of skin; Mantle cavity : Space between, visceral hump and mantle., Respiration and excretion by feather like gills in mantle cavity., Head has sensory tentacles. Radula a rasping organ for feeding in mouth., Are oviparous, dioecious, have indirect development., e.g., Plia, Pinctada, Octopus, Sepia, Loligo, Aplysia, Dentalium, Chaetopleura., , Phylum Echinodermata :, , , , , , , , , , , , Are spiny bodied organisms with endoskeleton of calcareous ossicles., Are exclusively marine, radially symmetrical in adult but bilaterally, symmetrical in larval stage. Organ system level of organisation., Triploblastic and coelomate., Digestive system complete. Mouth ventral, Anus on dorsal side., Food gathering, respiration, locomotion carried out by water vascular system., Excretory system is absent., Reproduction–sexual, sexes are separate., Fertilisation external. Development indirect (free swimming larva), e.g., Asterias, Cucumaria, Antedon, Echinus, ophiura., , Phyum Hemichordata :, , , , Represents small group of worm-like organisms., Was earlier placed as sub-phylum of Phyum Chordata., 41, , www.cleariitmedical.com

Page 21 :
, , , , , , , Bilaterally symmetrical, triploblastic and coelomate with organ system level, of organisation., Body cylindrical, has proboscis, collar and trunk., Circulatory System–open., Respiration by gills, excretion by proboscis gland., Sexes separate, external fertiliastion, indrect development., e.g, Balanoglossus, saccoglossus., , Phylum Chordata :, , , , , , , , , Presence of Notochord., Have dorsal hollow nerve chord., Have paired pharyngeal gill slits., Bilaterally symmetrical, triploblastic, coelomate, organ system level of, organisation., Heart is ventral., Post anal tail present, closed circulatory system., , (i) Sub-Phyla Urochordata /Tunicata, , , Notocohord present only in larval tail., e.g., Ascidia, Salpa, Doliolum, , (ii) Sub-phyla Cephalochordata, , , Notochord extends from head to tail (Persistent), e.g., Amphioxus., , (iii) Sub-Phyla Vertebrata, , , , , Have notochord only during embryonic period., Notochord gets replaced by bony or cartilaginous vertebral column., Have ventral muscular heart, kidneys for excretion and osmoregulation, paired, appendages (ins or limbs), , Vertebrata have two Division :, (a) Agnatha (Lacks Jaw) : Class : Cyclostomata,  Live as ectoparasites on some ishes.,  Have sucking and circular mouth without jaws.,  Have 6-15 paris of gill slits for respiration.,  No scales, no paired ins.,  Cranium and vertebral column is cartilagenous., 42, , www.cleariitmedical.com

Page 22 :
Marine, Migrate to fresh water for spawning and die after spawning.,  Larva returns to ocean after metamorphosis., e.g., Petromyzon, Myxine, (b) Gnathostomata (Bear Jaws)–divides into two super classes :, , , Super-class : Pisces, 1. Class : Chondrichthyes :,  Have cartilagenous endoskeleton, are marine with streamlined body.,  Mouth ventral.,  Gill slits without operculum (gill cover).,  Skin has placoid scales; jaws–very powerful.,  No air bladder, so swim constantly to avoid sinking.,  Teeth are backwardly directed, modiied placoid scales.,  Notochord is persistent throughout life.,  Two chambered heart; poikilotherms (cold-blooded),  Sexes separate; males have claspers on pelvic ins.,  Internal fertilisation; viviparous., e.g., Tarpedo, Trygon, Scoliodon, Pristis, Carcharodon, 2. Class : Osteichthyes,  Have bony endoskeleton, Aquatic,  Mouth is usually terminal. Body-Streamlined,  Four pairs of gill slits covered by operculum, heart two chambered, cold, blooded.,  Sking has cycloid/ctenoid scales.,  Have air bladder which regulates buoyancy.,  Sexes separate.,  Usually oviparous, fertilisation external.,  Development direct.,  e.g., Hippocampus, Labeo, Catia, Betla, Clarias, Exocoetus, , Sub-Phylum Vertebrata : Gnathostomata, Super Class : Tetrapoda, 1. Class : Amphibia,  Can live in aquatic as well as terrestrial habitats.,  Body divisible into head and trunk, paired limbs., 43, , www.cleariitmedical.com

Page 23 :
Skin moist. No scales.,  Tympanum represents ear. Eyes have eyelids.,  Cloaca is the common chamber where alimentary canal, urinary and, reproductive tracts open.,  Respiration by gills, lungs or skin.,  Heart is 3-chambered; cold-blooded; Sexes separate; fertilisation external.,  Oviparous. Indirect development.,  e.g., Bufo, Rana, Hyla, Salamandra, Ichthyophis, 2. Class : Reptilla,  Creep or crawl to locomote. Mostly terrestrial.,  Body has dry and corniied skin and epideremal scales or scutes.,  Tympanum represents ear.,  Limbs, when present, are two pairs,  Snakes and lizards shed, scales as skin cast.,  Heart 3-chambered but 4-chambered in crocodiles.,  Sexes Separate; fertilisation internal.,  Oviparous. Direct development.,  e.g., Testudo, Naja, Vipera, Calotes, Crocodilus, Hemidactylus, 3. Class : Aves,  Presence of feathers except lightless birds and beak (modiied jaws), without teeth.,  Forelimbs are modiied into wings.,  Hind limbs have scales, modiied for walking, swimmng or clasping.,  Skin is dry as no glands on skin except oil gland at base of tail.,  Endoskeleton bony with air cavities (pneumatic) and hollow bones to, assist in light.,  Crop and Gizzard—Additional chamber in digestive tract.,  Air sacs are connected to lungs to supplement respiration.,  Warm blooded (homoiothermous), Heart–Four chambered.,  Sexes separate, fertilization internal,  Oviparous. Direct development.,  e.g., Columba, Struthio, Pavo, Corvus, Neophron, Pstittacula Aptenodytes., 4. Class : Mammalia, , Have mammary glands to nourish young ones., , Have two pairs of limbs, adapted to perform special work., , Skin has hairs., , , 44, , www.cleariitmedical.com

Page 25 :
Points to Remember, Cell Theory : Cell Theory was formulated by Schleiden and Schwann, and, was modiied by Rudolf Virchow. Cell theory States., (A), , All living organisms are composed of cells and products of cells., , (B), , All cells arise from pre-exiting cells., , Cell : Cell is the tructural and functional unit of life., Prokaryotic Cell, , Eukaryotic Cells, , , , Generally small sized (1–10 µm), , , , Generally large sized (5–10 µm), , , , Well deined nucleus absent, , , , Well deined nucleus present, , , , Membrane bounded cell organelles, , , , Membrane bounded cell organelles, , absent, , , , , present, , DNA without histone protein, , , , DNA with histone protein, , e.g., Bacteria, Mycoplasma, Blue, , e.g., Amoeba, Euglena and other, , green Algae, , higher organism, , Gram Positive Bacteria, , Gram Negative Bacteria, , Bacteria that take up gram, , , , Stain. e.g., Bacillus, , Bacteria do not take up gram stain, e.g., Escherichia Coli, , PROKARYOTIC CELL :, Modification of cell envelope, , , Slime layer : Glycocalyx in form of loose sheath., , , , Capsule : Glycocalyx in form of thick and tough sheath., , , , Mesosomes : Extension of plasma membrane. These can be in the form of, vesicles, tubules and lamellae., , www.cleariitmedical.com

Page 26 :
Functions : Cell wall formation, DNA replication and distribution to daughter, cells, respiration, secretion processes, to increase surface area of plasma, membrane and enzyme content.,  Flagella : Extension of cell wall. It is composed of three structure–ilament,, hook and basal body. It help in motility of bacteria.,  Pili and imbriae : Surface structure of some bacteria which attaches them, to rocks in streams and to host tissues., Genetic Material : It is not covered by nuclear envelope. In addition to the, genomic DNA (the single chromosome/circular DNA), many bacteria have small, circular self replicating, double straned DNA which is called as plasmid, plasmid, contain genes like antibiotic resistance., , Eukaryotic cells, Possess an oragnized nucleus with nuclear envelope and have a variety of, complex locomotory and cytoskeletal structures., Cell Membrane — Singer and Nicolson (1972) gave ‘luid mosaic model’., According to this the quasi-luid nature of lipid enables lateral movement of, proteins within the overall bilayer; two types of proteins (Peripheral and integral, proteins) with cholesterol, glycolipids and glycoporteins. Erythrocyte membrane, has 52% protein and 40% lipids., Function—It is semi permeable and helps in transport of molecule across it., Passive transport, Active transport,  Transport of molecules from,  Transport of molecules from lower to, higher to lower concentration., higher concentration,  It do not utilise energy (ATP).,  It utilises energy (ATP), e.g., diffusion, e.g., Na+/k+ ATPase Pump., , Fluid Mosaic Model of Plasma Membrane฀, , www.cleariitmedical.com

Page 27 :
Cell Wall is non-living rigid structure which gives shape to the cell and, protects cell from mechanical damage and infection, helps in cell-to-cell interaction, and provides barrier to undesirable macromolecules., Cell wall of algae is made of cellulose, galactans, mannans and minerals like, calcium carbonate. Plant cell wall consists of cellulose, hemicellulose, pectins, and proteins., Middle lamella is made of calcium pectate which holds neighbouring cells, together., Plasmodesmata connect the cytoplasm of neighbouring cells., Endoplasmic Reticulum (ER), Consists of network of tiny tubular structure. ER divides the intracellular, space into two distinct compartments–luminal (inside ER) and extra luminal, (cytoplasm)., (i) Rough Endoplasmic Reticulum (RER) :,  Ribosomes attached to outer surface., Function :  Involved in protein synthesis and secretion., (ii) Smooth Endoplasmic Reticulum (SER) :  Lack ribosomes., Function  Site for synthesis of lipid., Golgi apparatus : First observed by Camillo Golgi (in 1898), Consist of cisternae stacked parallel to each other. Two faces of the organelle, are convex/cis or forming face and concave/trans or maturing face., Functions : Performs packaging of materials, to be delivered either to the, intra-cellar targets or secreted outside the cell. Important site of formation of, glycoproteins and glycolipids., Lysosomes :, Membrane bound vesicular structures formed by the process of packaging, in the golgi apparatus. Contain hydrolysing enzymes (lipases, proteases,, carbohydroses) which are active in acidic pH. Also called ‘Suicidal Bag’., Function : Intracellular digestion., Vacuoles : Member bound space found in the cytoplasm. Contain water, sap,, excretory product, etc. In plant cell, vacoule occupies 90% of space., Function : In plants tonoplast (single membrane of vacuole) faciliates, transport of ions and other substances., Contractile vacuole for excretion in Amoeba and food vacuoles formed in, protists for digestion of food., , www.cleariitmedical.com

Page 29 :
Ribosomes, Composed of RNA and proteins; without membrane. Eucaryotic ribosomes, are 80S. S = Svedberg’s unit), Function : Site of protein synthesis., Cytoskeleton : Network of ilaments., Proteinaceous structure in cytoplasm made up of microtubules and micro, ilaments., Function : Mechanical support, motility, maintenance of the shape of the cell., Cilia and Flagella, Cilia are small structures which work like oars which help in movement., Flagella are longer and responsible for cell movement. They are covered, with a plasma membrane. Core is called axoneme which has 9 + 2 arrangement, of axonemal microtubules., , Centrosome and Centrioles, Centrosome contains two cylindrical structures called centrioles. Surrounded, by amorphous pericentriolar material. Has 9 + 2 arrangement. Centrioles form the, basal body of cilia or lagella and spindle ibres for cell division in animal cells., They produces spindle apparatus during cell divison., Nucleus : With double membrane with perinuclear space and nuclear pores;, has Chromatin, nuclear matrix and nucleoli (site for rRNA synthesis). (Named, by Robert Brown – 1831), Chromatin DNA + nonhistone proteins. (Named by Flemming), Nucleoplasm – Nucleolus + Chromatin, Nulear membrane—It is with perinuclear space and nucleopores., Chromosomes—DNA/RNA + Histone protein/Nonhistone protein., Centromere : Primary constriction–disc is known as kinetochores., No nucleus in Erythrocyctes (RBC) of mammals and sieve tubes in vascular, plants., Chromosomes (on basis of position of centromere) :, Metacentric : Middle centromere., Sub-metacentric : Centromere nearer to one end of chromosomes., Acrocentric : Centromere situated close to its end., Telocentric :Has terminal centromere., Satellite : Some chromosomes have non-staining secondary constructions at, a constant location, which gives the appearance of small fragment called satellite., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 30 :
Points to Remember, Biomolecules : All the carbon compounds that we get from living tissues., Biomicromolecules : Molecules which have molecular weights less than, one thousand dalton. They are also known as monomers., Biomacromolecules : Have molecular weight more than 10000 daltons, (generally 10,000 deltons and above). They are generally polymers., Biomacromolecules : A biomolecule a with molecular weight in the, range of ten thousand daltons and above; found in acid insoluble fraction. e.g., polysaccharides, nucleic acids, proteins and lipids., , Primary and secondary metabolites :, , , , , Primary metabolites have identiiable functions and play important roles in, normal physiological process eg. Amino acids, nitrogenous bases, proteins, and nucleic acid., Secondary metabolites are product of certain metabolic pathways from, primary metabolites, eg. carotenoids, drugs, alkaloids, essential oils, rubber,, gum, cellulose and resins etc., Amino acids : Organic compounds containing an amino group and one, carboxyl group (acid group) and both these groups are attached to the same, carbon atom called α carbon and so they are called amino acids., , e.g. (1) In Glycine R = H, (2) In alanine R = CH3, (3) In serine R = CH2 – OH, , www.cleariitmedical.com

Page 31 :
, , Twenty types of amino acids., Amino acid exists in Zwitterionic form at different pHs., R, R, R, |, |, |, (A), , , , (B), (C), (Zwitterionic form), Based on number of amino and carboxyl groups, amino acids can be :, (i) Aromatic–Tryptophan, phenylalanine and Tyrosine are aromatic (give, smell) amino acids., Amino Acids, Polar, Acidic, e.g. aspartic acid, , Basic, e.g., Arginine, , Neutral, e.g. valine, Proline, , glutamic acid, (ii) Non Polar—Glutamine, tyrosine, serine, , Lipids :, Lipids are not strictly macromolecules as their molecular weight do not, exceed 800 Da but form a part of the acid insoluble pool.,  Water insoluble, containing C, H, O.,  Fats on hydrolysis yield fatty acids.,  Fatty acid has a carboxyl group attached to an R group (contains 1 to 19, carbons).,  Fatty Acids : Saturated : With single bonds in carbon chain, e.g., Palmitic, acid, butyric acid., Unsaturated : With one or more double bonds, e.g., oleic acid, linoleic acid.,  Glycerol : A simple lipid, is trihydroxy propane., , , , Some lipid have fatty acids esteriied with glycerol., Example of fatty acid (Palmitic acid) (CH3—(CH2)14—COOH), , 92, , www.cleariitmedical.com

Page 32 :
, , They can be monoglycerides, diglycerides and triglycerides., 1, , 2, , 3, , , , Triglyceride (R1, R2, R3 are alkyl groups in fatty acids.), Phospholipids (Lecithin) found in cell membrane and lipids made complex, structure in neural tissue., Phospholipids are compound lipids with phosphorus and a phosphorylated, organic compound e.g., Lecithin., Nitrogen bases, (Carbon compounds with heterocyclic rings), Purine : Adenine, Guanine,, , Pyrimidine : Cytosine, Uracil, Thymine., , Nucleoside : Nitrogenous base + Sugar e.g. Adenosine, guanosine., Nucleotide : Nitrogenous base + Sugar + Phosphate group. e.g. Adenylic, acid, Guanylic acid. Thymidylic acid., Nucleic acids : Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)., DNA structure (Watson and Crick Model) : DNA is a right handed, double, helix of two polynucleotide chains, having a major and minor groove. The two, chains are antiparallel, and held together by hydrogen bonds (two between A, and T and three between C and G). The backbone is formed by sugar-phosphatesugar chain. The nitrogen bases are projected more or less perpendicular to this,, backbone and face inside. The pitch is 34A°. At each step of ascent, the strand, turns 36°. The rise per base pair is 3.4°A, so one full turn involves ten base pairs., Protein : proteins are polypeptides., , , They are polymers of aminoacids linked by peptide bond., , , , Is a heteropolymer (different monomers repeating ‘n’ number of times)., , , , For functions of proteins refer Table 9.5, Page no. 147 NCERT, Text Book, of Biology for Class XI., , 93, , www.cleariitmedical.com

Page 33 :
Structure of Proteins, (a) Primary structure : Is found in the form of linear sequence of amino acids., First amino acid is called N-terminal amino acid and last amino acid is called, C-terminal amino acid., (b) Secondary structure : Polypeptide chain undergoes folding or coiling which, is stabilized-by hydrogen bonding. Right handed helices are observed; e.g.,, ibrous protein in hair, nails., (c) Tertiary structure : Long protein chain is folded upon itself like a hollow, woollen ball. Gives a 3-dimensional view of protein, e.g., myosin., (d) Quaternary structure : Two or more polypeptides with their foldings and, coilings are arranged with respect to each other, e.g., Human haemoglobin, molecule has 4 peptide chains - 2 α and 2 β Subunits., Monosaccharides are joined by glycosidic bond, right end is reducing and, left end is non reducing, Polysaccharides : Are long chain of polymers of monosaccharides., (a) Starch : Store house of energy in plant tissues. Forms helical secondary, structures, made of only glucose monomers., (b) Cellulose : Homopolymer of glucose. It does not certain complex helices., Cotton ibre is cellulose., (c) Glycogen : Is a branched homopolymer, found as storage polysaccharide in, animals., (d) Inulin : Is a polymer of fructose., (e) Chitin : Chemically modiied sugar (amino-sugars) N-acetyl galactosamine, form exoskeleton of arthropods; heterpolymer., , Metabolic Pathways :, (a) Anabolic pathways : Lead to formation of more complex structure from a, simpler structure with the consumption of energy, e.g., Protein from amino, acids., also known as biosynthetic pathways., (b) Catabolic pathway : Lead to formation of simpler structure from a complex, structure, e.g., Glucose → Lactic Acid + energy, The most important energy currency in living systems is ATP (adenosine, tri – phosphate)., “There is no uncatalysed metabolic conversion in living system”, The living state is a non-equilibrium steady state to be able to perform work., Without metabolism, there cannot be a living state., 94, , www.cleariitmedical.com

Page 34 :
Bonds linking monomers in a polymer, Peptide bond—formed between the carboxyl (–COOH) group of one amino, acid, and the amino (– NH2) group of the next amino with the elimination of water, moiety, (dehydration)., Glycosidic bond—bond formed between two carbon atoms of two adjacent, monosaccharides., by dehydration., Phosphodiester bond—bond formed in nucleic acids where in a phosphate, moiety links the 3-carbon of one sugar of one nucleotide to the 5-carbon of the, sugar of the succeeding nucleotide. (The bond between phosphate group and, hydroxyl group of sugar), Ezymes : Are biocatalyst.,  Almost all enzymes are proteins.,  Ribozymes–Nucleic acid that behave like enzymes.,  Has primary, secondary and tertiary structure.,  Active site of an enzyme is a crevice or pocket into which substrate its.,  Enzymes get damaged at high temperatures.,  Enzymes isolated from thermophilic organisms (live under high temperatures), are thermostable.,  Enzymes accelerate the reactions many folds.,  Enzymes lower the activation energy of reactions. (Fig. 9.6, Page no. 156,, NCERT Text Book of Biology for Class XI).,  E + S == ES → EP → E + P, where E = Ezymes, S = Substrate, P = Product, , Factors affecting enzyme activity :, (a) Temperature : Show highest activity at optimum temperature. Activity, declines above and below the optimum value., (b) pH : Enzymes function in a narrow range of pH. Highest activity at optimum, pH. (Fig. 9.7, Page no. 157, NCERT, Text Book of Biology for Class XI)., 95, , www.cleariitmedical.com

Page 35 :
(c) Concentration of substrate : The velocity of enzymatic reaction rises with, increases in substrate concentration till it reaches maximum velocity (Vmax)., Further increase of substrate does not increase the rate of reaction as no free, enzyme molecules are available to bind with additional substrate., KM value : The substrate concentration at which Vmax x is half of a reaction., Enzyme inhibition : When the binding of a chemical shuts off enzyme, activity, the process is called inhibition and chemical is called inhibitor., Competitive inhibition : Inhibitor closely resembles the substrate in its, molecular structure and inhibits the enzyme activity. E.g., inhibition of succinic, dehydrogenase by malonate. (Actual is succinic acid)., , Classification of enzymes :, 1. Oxidoreductase/dehydrogenases : Catalyse oxidoreduction between 2, substrates. S reduced + S′ oxidised → S′ oxidised + S′ reduced., 2. Transferases : Catalyse transfer of a group between a pair of substrates., S – G + S′ → S + S′ – G, 3. Hydrolases : Catalyse hydrolysis of ester, ether, peptide, glycosidic, C–C,, P-N bonds., 4. Lyases : Catalyse removal of groups from substrates by mechanisms other, than hydrolysis. Leave double bonds., 5. Isomerases : Catalyse inter-conversion of optical, geometrical or positional, isomers., 6. Ligases : Catalyse linking together of 2 compounds., C–O, C–S, C–N, P–O, Co-factors : Enzymes becomes catalytically become active when it binds, to non protein constituent called co-factors. Protein portion of enzyme is, called apoenzyme., , , Prosthetic group : These are organic compound which tightly bound to the, apoenzyme., e. g., Haem is prosthetic group in peroxidase and catalase., , www.cleariitmedical.com

Page 36 :
, , Coenzyme : These are organic compounds whose association with the, apoenzyme is only transient, usually occurring during the course of catalysis., e.g., Coenzyme Nicotinamide adenine dinucleotide (NAD) and NADP, contain vitamin niacin., , , , Metal ions : Metal ions form coordination bond with side chains at the, active site and at the same time form one or more coordination bond with, substrate., e.g. zinc in enzyme carboxy peptidase., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 37 :
Points To Remember, Cell cycle : The sequence of events by which a cell duplicates its genome,, synthesises the other constituents of the cell and eventually divides into two, daughter cells., Interphase (G1 phase + S phase + G2 Phase), , Phases of cell cycle, , Karyokinesis (division of nucleus), M Phase (Mitosis phases), Cytokinesis (division of cytoplasm), , Interphase : (Resting Phase), , , G1 Phase : Cell metabolically active and grows continuously but does not, replicate DNA, , , , S Phase : DNA synthesis occurs, DNA content increases from 2C to 4C, but, the number of chromosomes remains same i.e., 2n., , , , G2 Phase : Proteins are synthesised in preparation for mitosis while cell, growth continues., M Phase (Mitosis Phase) : Starts with nuclear division, corresponding to, , separation of daughter chromosomes (karyokinesis) and usually ends with division, of cytoplasm, (cytokinesis)., Quiescent stage (G0) In adult animals cells that do not divide and exit G1, phase to enter an inactive stage called G0. Cells at this stage remain metabolically, active but do not proliferate., e.g., Heart cells, , www.cleariitmedical.com

Page 38 :
Mitosis, Since the number of chromosomes in the parent and progeny cells is the, same, it is called as equational division. Mitosis is divided into four sub stages., 1. Prophase : (i) Replicated chromosomes, each consiting of 2 chromatids,, condense and become visible., (i) Microtubules are assembled into mitotic spindle., (iii) Nucleolus and nuclear envelope disappear., (iv) Centriole moves to opposite poles., 2. Metaphase : (i) Spindle fibres attached to kinetochores (small disc-shaped, structures at the surface of centromere) of chromosomes., (ii) Chromosomes line up at the equator of the spindle to form metaphase, plate., 3. Anaphase : (i) Centromeres split and chromatids separate., (ii) Chromatids move to opposite poles due to shortening of spindle ibres., 4. Telophase : (i) Chromosomes cluster at opposite poles., (ii) Nuclear envelope assembles around chromosomes clusters’., (iii) Nucleolus, Golgi Complex, E.R. reforms., , www.cleariitmedical.com

Page 39 :
Cytokinesis : Is the division of protoplast of a cell into two daughter cells, after karyokinesis (nuclear division), Animal Cytokinesis :, Appearance of furrow in plasma membrane which deepens and joins in the, centre, dividing cell cytoplasm into two., Plant cytokinesis : Formation of new cell wall begins with the formation, of a simple precursor — cell plate which represents the middle lamella between, the walls of two adjacent cells., , , When karyokinesis is not followed by cytokinesis, a multinucleated condition, arises. This is called syncytium., , Significance of Mitosis :, 1., 2., 3., 4., , Growth-addition of cells., Maintenance of surface/volume ratio. Maintain Nucleo–cytoplasmic ratio., Maintenance of chromosomes number., Regeneration., , www.cleariitmedical.com

Page 40 :
5. Reproduction in unicellular organisms, lower plants and some insects., 6. Repair and wound healing., 7. Vegetative reproduction in plants takes place by mitosis., , Meiosis :, , , , , , , , , , , Specialised kind of cell division that reduces the chromosomes number by, half. hence it is called reductional division., Occurs during gametogenesis in plants and animals., Involves two sequential cycles of nuclear and cell division called Meiosis I, and Meiosis II., It results in 4 haploid daughter cells., Interphase occurs prior to meiosis which is similar to interphase of mitosis, except the S phase is prolonged., , Meiosis I, Prophase I : Subdivided into 5 phases., (i) Leptotene :, Chromosomes make their appearance as single stranded structures., , Compaction of chromosomes continues., (ii) Zygotene :, , Homologous chromosomes start pairing and this process of association, is called synapsis., , Chromosomal synapsis is accompanied by formation of Synaptonemal, complex., , Complex formed by a pair of synapsed homologous chromosomes is, called bivalent or tetrad., (iii) Pachytene : Crossing over occurs between non-sister chromatids of, homologous chromosomes. The enzymes involved in the process is, ‘recombinase’. Recombination between homologous chromosomes is, completed. Exchange of genetic material., (iv) Diplotene : Dissolution of synaptonemal complex occurs and the recombined, chromosomes separate separate from each other except at the sites of crossing, over. These X-shaped structures are called chaismata. In oocytes of some, vertebrates diplotene can last for month or years., , , www.cleariitmedical.com

Page 41 :
(v) Diakinesis : Terminalisation of chaismata., , Chromosomes are fully condensed and meiotic spindles assembled., , Nucleolus disappear and nuclear envelope breaks down., Metaphase I : Bivalent chromosomes align on the equatorial plate.,  Microtubules from opposite poles of the spindle attach to the pair of, homologous chromosomes., Anaphase I : Homologous chromosomes, separate while chromatids remain, associated at their centromeres., , Telophase I :, Nuclear membrane and nucleus reappear.,  Cytokinesis follows (diad of cells)., Interkinesis : Stage between two meiotic divisions, (meiosis I and meiosis II), generally short lived., Meiosis II: (It resembles the normal mitosis)., , , Prophase II, Nuclear membrane disappears.,  Chromosomes again become compact., Metapahse II,  Chromosomes align at the equator.,  Microtubules from opposite poles of spindle get attached to kinetochores of, sister chromatids., Anaphase II,  Simultaneous splitting of the centromere of each chromosome, allowing, them to move towards opposite poles of the cell., Telophase II,  Two groups of chromosomes get enclosed by a nuclear envelope.,  Cytokinesis follows resulting in the formation of tetrad of cells i.e., 4 haploid, cells., , , Significance of Meiosis, 1. Formation of gametes : In sexually reproducing organisms., 2. Genetic variability : Variations are very important for evolution., 3. Maintenance of chromosomal number : By reducing the chromosome, number in gametes. Chromosomal number is restored by fertilisation of, gametes., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 42 :
Points To Remember, Translocation (Long distance transport) : Transport of substances in, plants over longer distances through the vascular tissue (Xylem and Phloem), The transport of water and mineral in Xylem is unidirectional while transport of, organic and mineral nutrients in phloem is multi-directional., Means of transport (Short distance transport) : The transport of material, into and out of the cells is carried out by a number of methods. These are diffusion,, facilitated diffusion and active transport., (i) Diffusion : Diffusion occurs from region of higher concentration to region, of lower concentration across the permeable membrane. It is passive and slow, process. No energy expenditure takes place., Factors affecting diffusion : Permeability of membrane, Temperature,, pressure, gradient of concentration and the size of substances., (ii) Facilitated diffusion : The diffusion of hydrophilic substances along, the concentration gradient through ixed membrane transport protein without, involving energy expenditure. For this the membrane possess aquarporins and, ion channels. No ATP energy is utilized in this process., Porins—The proteins that form huge pores in the outer membranes of the, plastids, mitochondria and some bacteria which allow the small size molecules, to pass through., Aquaporins—Proteins that facilitate diffusion of water molecules through/, across the plasma membrane of cell., Methods of Facilitated Diffusion, Symport, , Antiport, , Uniport, , (Two molecules cross the, (Two molecules move (Single molecule moves, membrane in the same, in opposite direction at across membrane indpendirection at the same time.) the same time.), dent of other molecules.), , www.cleariitmedical.com

Page 43 :
Transport Proteins—They are present in the membrane. They allow the, passage of substances through membrane., (i) Carrier Proteins—They bind to the particular solute particle to be, transported and deliver these to other side of membrane., (ii) Channel Proteins—Ion Channel—They are speciic for different ions like, K+, Cl–,, Water Channel—Surrounded by eight proteins called aqua protein and, allow passage of water or water soluble substance., (iii) Active transport : Active transport is carried by the movable carrier, proteins (pumps) of membrane. Active transport uses energy to pump molecules, against a concentration gradient from a low concentration to high concentration, (uphill-transport). It is faster than passive transport., , Different Transport Mechanisms, S., No., 1., 2., 3., , , , , , , , , , , , Property, , Required Special, membrane protein, Uphill transport, Requires ATP Energy, , Simple, Diffusion, , Faciliated, Transport, , Active, Transport, , No, , Yes, , Yes, , No, No, , No, No, , Yes, No, , Water potential—(ψw)–Greater the concentration of water in a system,, greater is its kinetic energy and greater is the water potential. It is measured, in pascal (Pa). or mega pascal., If two systems are in contact, then there is movement of water from the, solution with higher potential to lower water potential., Solute potential—(ψs)–Magnitude of lowering of water potential, when a, solute is added to the water., Pressure Potential—(ψp)—Magnitude of increase of water potential, when, pressure greater than atmospheric pressure is applied to pure water or a, solution., Water potential of pure water is zero (0)., Solute potential is always negative (–) and pressure potential is always, positive (+)., ψw = ψs + ψp, , www.cleariitmedical.com

Page 44 :
Osmotic Pressure—External pressure applied to prevent the diffusion of, water. It depends upon solute concentration.,  Numerically, osmotic pressure is equal to osmotic potential. Osmotic pressure, has positive (+) sign. Osmotic potential has negative (–) sign., Turgor Pressure—Due to osmotic entry of water, the protoplasm of a plant, cell presses the cell wall towards the outside with a force, it is called Turgor, Pressure., Diffusion Pressure—The pressure exerted by the tendency of the particles to, diffuse from the area of higher concentration to lower concentration. It is directly, proportional to the concentration of particles of diffusing substance., Osmosis : Osmosis is movement of solvent or water molecules from the, region of their higher diffusion pressure or free energy to the region of their lower, diffusion pressure of free energy across a semipermeable membrane., Water molecules move from higher water potential to lower water potential, until equilibrium is reached., Plasmolysis : Process of shrinkage of protoplast in a cell due to exosmosis, in hypertonic solution. If a plasmolysed cell is placed in water or a hypotonic, solution it becomes turgid., Hypotonic solution : The external solution which is more dilute than the, cytoplasm., Hypertonic solution : The external solution, which is more concentrated, than the cytoplasm., Isotonic solution : When the external solution balances the osmotic pressure, of the cytoplasm., Casparian strip : It is the tangential as well as radial walls of endodermal, cells having the deposition of water impermeable suberin., Imbibition : Imbibition is the phenomenon of absorption of water by the, solid particles of an adsorbent causing it to enormously increase in volume without, forming a solution., , , Some examples of Imbibition :, (i) If a dry piece of wood is placed in water, it swells and increases in its volume., (ii) If dry gum or pieces of agar-agar are placed in water, they swell and their, volume increases., (iii) When seeds are placed in water they swell up., (iv) Swelling of wooden door during rainy season., , Conditions essential for imbibition, 1. Water potential gradient between the surface of the adsorbent and the imbibed, liquid, is essential., 2. Afinity between the adsorbent and the imbibed liquid., , www.cleariitmedical.com

Page 45 :
Transport of water in plants : Water is absorbed by root hairs by diffusion., Then water moves upto xylem by two pathways–apoplast and symplast pathway., Apoplast Pathway—Movement occurs through the intercellular spaces or, walls of the cell, without entering the cytoplasm. This movement is fast. In roots,, movement of water occurs via apoplast except at the carparian strip, most of water, enters through apoplast., Symplast Pathway—Water enters the cell through cell membrane and travels, intercellularly through plasmodesmata. This movement is slow. At casparian strip, region water moves through symplast., Symplastic Pathway (through cells), Cortex, Endodermis, Phloem, Root Hair, Xylem, Pericycle, Casparian Strip, Epidermis, Apoplastic Pathway, (through cell wall only), , Apoplastic And Symplastic Pathways of Water Transport, Ascent of Sap—Upward movement of water in the form of dilute solution of, mineral ions from roots to the top aerial parts of plants through tracheary elements, of xylem against the gravitational force is called ascent of sap. It involves two, theories—, (i) Cohesion—Tension-transpirtation pull theory., (ii) Root pressure theory., (1) Cohesion-Tension-transpiration pull theory—, (i) Continuity of water column—The transport of water to the top of trees, occurs through xylem vessels. The forces of adhesion and cohesion maintain a, thin and unbroken column of water in the capillaries of xylem vessels through, which it travels which is travels upward. Water is mainly pulled by transpiration, from leaves., (ii) Transpiration Pull—Transpiration accounts for loss of 99% of water in, the form of water vapours the surface of leaves. The loss is mainly through stomata.,  Pull of water as a result of tension created by transpiration is the major diving, force of water movement upward in a plant., Three physical properties of water which affect the ascent of xylem sap due, to transpiration pull., 112, , www.cleariitmedical.com

Page 46 :
(iii) Cohesion force or Tensile strength of water—,  Cohesion—Mutual attraction between water molecules.,  Adhesion—Attraction of water molecules to polar surface.,  Surface tension—Attraction of water to each other in liquid phase to a, greater extent than to water in gaseous phase., (2) Root pressure Theory : A hydrostatic pressure existing in roots which, pushes the water up in xylem vessels upto certain height to herbaceons plant., Guttation : The water loss in its liquid phase in the form of water droplets at, night and early morning through special openings of vein near the tip of leaves., These opening are called hydathodes., Transpiration : The loss of water through stomata of leaves and other aerial, parts of plants in form of water vapours., Factors affecting transpiration : Temperature, light, relative humidity, wind, speed, number and distribution of stomata, water status of plant, canopy structure., Signiicance of transpiration—Advantages—Helps in ascent of sap removal, of excess water, cooling effect, distribution of mineral salts, supply water for, photosynthesis., Disadvantages—May cause reduced growth, wilting (loss of turgidity),, reduced yield and waste of energy., Since there are advantages as well as disadvantages of transpiration so—, ‘Transpiration is called a necessary evil’., Opening and closing of stomata—Mechanism of opening and closing of, stomata involves two steps—, (i) Change to the turgidity of gaurd cells., (ii) Orientation of cellulose microibrils in the cell wall of gaurd cells., Endosmosis—When a cell is placed in water or hypotonic solution, water, enters into the cell. This in called endosmosis. Due to it the volume of cell increases, and it creates turgor pressure., Exosmosis—When a cell is placed in hypertonic solution, water comes out, of the cell, this is called exosmosis. It decreases volume of the cell., Uptake and transport of mineral nutrients—Ions are absorbed by the roots, by passive and active transport. The active uptake of ions require ATP energy., Speciic proteins in membranes of root hair cells activity pump ions from the soil, into the cytoplasm of epidermal cells and then xylem. The further transport of ions, to all parts of the plant is carried through the water stream. Older dying leaves, export much of their mineral content to younger leaves. Elements phosphorus,, sulphur, nitrogen and potassium are most readily mobilised., , www.cleariitmedical.com

Page 47 :
Mass low : Mass low is the movement of substances (water, minerals and, food) in bulk from one point to another as a result of pressure differences between, two points., , The pressure or mass flow Hypothesis :, Leaf Mesophyll Cells, Photosynthesis, ↓, Glucose, ↓, Sucrose, ↓, Rise in Osmotic Pressure, ↓, Endosmosis, ↓, Rise in T.P. of Mesophyll Cells, ↓, Mass low of H2O and Sucrose due to turgor gradient, ATP, ADP + ip, “In masse” comes in companion cell, and then into sieve tube cells, ↓, 114, , www.cleariitmedical.com, , Loading

Page 48 :
Water comes in sieve tube cell from, Xylem and increase turgor Pressure gradient, ATP, ADP + i, Sucrose comes to Root cell and, convert into starch or energy or get, consumed in Respiration, , Unloding, , ↓, Decrease in O.P. of Root Cells, ↓, Water moves to Root Xylem, Mycorrhiza—A mycorrhiza is a symbiotic association of a fungus with a, root system. The fungal hyphae absorb mineral ions and water from the soil, and, provide them to the roots of plant, in turn the roots provide sugars and nitrogen, containing compounds to the mycorrhizae., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 49 :
Points To Remember, Autotroph : An organism that sythesize its required nutrients from simple, and inorganic substance; Example—plants, blue green algae (cyanobacteria), Heterotroph : An organism that cannot synthesise its own nutrients and, depend on others. Example—Bacteria, protists, members of animalia., Biological nitrogen ixation: Conversion of atmospheric nitrogen into, organic compounds by living organisms., Chlorosis : Yellowing of leaves due to loss of chlorophyll., Nitriication : Conversion of ammonia (NH3) into nitrite and then to nitrate., Denitriication : A process of conversion of nitrate into nitrous oxide and, nitrogen gas (N2)., Leg-hemoglobin : Pinkish pigment found in the root nodules of legumes., It acts as oxygen scavenger and protects the nitrogenase enzyme from oxidation., Flux : The movement of ions is called lux. Inlux is inward movement of, ions into the cells and eflux is the outward movement of ions., Inhibition of cell division : Deiciency of N, K, S. and Mo., Necrosis : Death of tissues particularly leaf tissue due to deiciency of Ca,, Mg, Cu, K., Delayed Flowering : due to deiciency of N, S, Mo., Mineral Nutrition : Plants require mineral elements for their growth and, development. The utilization of various absorbed ions by a plant for growth and, development is called mineral nutrition of the plant., Hydroponics : Soil-less culture of plants, where roots are immersed, in nutrient solution (without soil) is called hydroponics. The result obtained, from hydroponics may be used to determine deiciency symptoms of essential, elements., , www.cleariitmedical.com

Page 50 :
Active Transport : Absorption occuring at the expense of metabolic energy., Passive Transport : Absorption of minerals with concentration gradient by, the process of diffusion without the expense of metabolic energy., , Essential Elements, Macronutnents, Macronutrients are present in plant, tissues in concentrations of more, than 10 m mole Kg–1 of dry matter., C, H, O, N, P, K, S, Ca, Mg, , Micro-nutrients, Micro-nutrients are needed in very, low amounts : less than 10 m mole, Kg – 1 matter., Fe, Mn, Cu, Mo, Zn, B, Cl, Ni, , In addition to the 17 essential elements, Na, Si, Co and Si are required by, some higher plants., , Criteria for essentiality :, 1. The element must be necessary for supporting normal growth and reproduction., 2. Requirement must be speciic and not replaceable by another element., 3. The element must be directly involved in the metabolism of the plant., Role of Minerals Elements in Plants, MACRO NUTRIENTS, Element, , Obtained as, , Nitrogen (N), , Mainly as, some Constituent of, +, as NO2 or NH4, proteins, nucleic, acids, vitamins and, hormones., , Stunted growth, Chlorosis,, dormancy of, causal buds., , Phosphorus (P), , Phosphate ions, , Poor growth of, plant., , www.cleariitmedical.com, , Functions, , Constituent of cell, membrane. Required, for the synthesis, of nucleic acids,, nucleotides, ATP, NAD and NADP, for phosphorylation reactions., , Deiciency, symptoms, , Leaves dull green,, delay in seed, germination purple, or red spots on, leaves, premature, leaf fall.

Page 51 :
Potasium (K), , K+, , Calcium (Ca), , Ca2+, , Helps to maintain an, anion-cation balance, in cells. Involved in, protein synthesis, in, opening and closing, of stomata; activation, of enzymes; maintenance of turgidity of, cells., Required in formation, of mitotic spindle;, involved in normal, functioning of cell, membranes; activates, certain enzymes; as, calcium pectate in, middle lamella of the, cell wall., Activates enzymes in, phosphate metabolism,, constituent of, chlorophyll; maintains, ribosome structure., , Magnesium (Mg) Mg2+, , Sulphur (S), , Stunted growth;, yellow leaves, edges of, leaves; mottled, appearance of, leaves. Premature, death., Stunted growth,, chlorosis of young, leaves., , Chlorosis between, the leaf veins, narcosis purple, colours spots on, older leave, , Constituent of two, Chlorosis of, amino-acids-Crysteine younger leaves,, and methionine and, stunted growth, proteins, coenzymes,, vitamins and, ferredoxin., , MICRO NUTRIENTS, Element, , Obtained as, , Functions, , Deiciency, symptoms, , Iron (Fe), , Fe3+, , Constituent of, Ferredoxin and, cytochrome; needed, for synthesis of, chlorophyll., , Chlorosis of, leaves, , Activates certain, enzymes involved, in photosynthesis,, respiration and nitrogen, metabolism., , Chlorosis, grey, spots on leaves., , Manganese (Mn) Mn2+, , www.cleariitmedical.com

Page 52 :
Zinc (Zn), , Zn2+, , Activates various, enzymes like, carboxylases. Required, for synthesis of auxins., , Malformation of, leaves, , Copper (Cu), , Cu2+, , Activates certain, enzymes. Essential for, overall metabolism, , Stunted growth,, inter-veinal, chlorosis in leaves., Necrosis of the tip, of young leaves,, die back of shoot., , Boron (B), , BO33–, B4O72–, , Required for uptake, of water and Ca, for, membrane functioning,, pollen germination, cell, elongation carbohydrate, translocation., , Molybdenum, (Mo), , Chlorine (Cl), , MoO22+, (molybdate ions), , Cl–, , Death of stem, and root apex,, loss of a foical, dominance,, abscission of, lowers, small size, of fruits, Activates certain, Nitrogen, metabolism., deiciency interveinal chlorosis, retardation of, growth, Maintains solute, Wilted leaves;, concentration along, stunted root, with Na+ & K+; maintain growth and, anion-cation balance, reduced fruiting., in cells; essential for, oxygen evolution in, photosynthesis., , Critical Concentration : The concentration of the essential element below, which plant growth is retarted. The element is said to be deicient when present, below the critical concentration., Deiciency symptoms : Chlorosis, stunted growth, premature fall of leaves, and buds and inhibition of cell division., Toxicity of micronutrient : Any mineral ion concentration in tissues that, reduces the dry weight of tissues by 10% is considered toxic. Toxicity of one, element may lead to deiciency of other element since the former may inhibit the, uptake of latter., e.g., Mn competes with Fe, Mg for uptake and also inhibits Ca, translocation to shoot apex. Therefore Mn toxicity symptoms are actually same, as deiciency symptoms of Fe, Mg and Ca., , www.cleariitmedical.com

Page 54 :
The Nitrate so formed can be easily absorbed by the plants and transported, to leaves. In leaves, nitrate is reduced to ammonia to form amino-acids, because, nitrate can not used by plants as such., NO3, , –, , Nitrate reductase, , NADH2 NAD, , Nitrite, Reductase, , –, , NO2, , H2O, , NO3, , Amino acid, Synthesis, , NADH2 NAD, , Denitriication—Process of reduction of the nitrate present in soil to nitrogen., It is carried out by bacteria like Pseudomonas and Thiobacillus., Biological Nitrogen Fixation—Reduction of nitrogen to ammonia by living, organisms. Certain prokaryotes are able to ix nitrogen because of presence of, ‘nitrogenase’ enzyme in them., , Nitrogen fixing microbes may be, (a), , Free living—(i) Aerobic—Azotobacter, (ii) Anaerobic—Rhodospirillum, (b) Cyanobacteria—Nostoc, Anabaena, (c) Symbiotic—(i) With leguminous plants—Rhizobium, (ii) With non-leguminous plants—Frankia, Enzyme nitrogenase—The enzyme nitrogenase is Mo-Fe protein and, catalysis the conversion of atmospheric nitrogen to ammonia (First stable product, of nitrogen ixation), Leg-hemoglobin—A pink colour pigment, similar to hemoglobin of, vertebrates and functions as an oxygen scavenger and protects nitrogenase from, oxygen., N2 + 8e+ + 8H+ 16ATP dinitrogenase 2NH3 + H2 + 16 ADP + 16 Pi, ———→, , Steps of nodule formation :, (a) Rhizobium bacteria present in soil contact a susceptible root hair., (b) Infection of the root hair cause it to curve and deformed due to chemical, secretion., (c) An infection thread is produced carrying the bacteria into the cortex of the, root., (d) The bacteria get modiied into rod-shaped bacteria and cause inner cortical, and pericycle cells to divide plant produce cytokinin and auxin to stimulate, cell division and enlarge to form nodules., 126, , www.cleariitmedical.com

Page 55 :
(e) Division and growth of cortical and pericycle cells lead to nodule formation., , (Refer Figure 12.4 page 203 NCERT Text Book), , Mechanisms of N2 fixation, It require 3 components—, (a) A strong reducing agent like FADH2, NADPH2, (b) Nitrogenase enzyme, (c) ATP (as energy service), , Steps, (a) Formation of Diamide, (b) Formation of Hydrazine (N2H4), (c) Formation of Ammonia,, See Fig. 12.5 Page 203 NCERT, , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 56 :
Higher Plants, Points To Remember, Photosynthesis : Photosynthesis is an enzyme regulated anabolic process of, manufacture of organic compounds inside the chlorophyll containing cells from, carbon dioxide and water with the help of sunlight as a source of energy., 6CO 2 + 12H 2 O, , Sun Light, C6 H12 O6 + 6H 2 O + 6O 2 ↑, Chlorophyll + enzymes, , Historical Perspective, Josheph Priestley (1770) : Showed that plants have the ability to take up, CO2 from atmosphere and release O2. (Candle with bell jar and mouse expt.), Jan Ingenhousz (1779) : Release of O2 by plants was possible only in sunlight and only by the green parts of plants. (Expt. with aquatic plant in light & dark), Theodore de Saussure (1804) : Water is an essential requirement for, photosynthesis to occur., Julius Von Sachs (1854) : Green parts in plant produce glucose which is, tored as tarch., T.W. Engelmann (1888) : The efect of diferent wavelength of light on, photosynthesis and plotted the irt action spectrum of photosynthesis., C.B. Van Niel (1931) : Photosynthesis is essentially a light dependent, reaction in which hydrogen from an oxidisable compound reduces CO2 to form, sugar. He gave a simpliied chemical equation of photosynthesis., , 2H 2 A + CO 2, , Sun Light, , 2A + CH 2 O + H 2 O, , Hill (1937) : Evolution of oxygen occurs in light reaction., Calvin (1954-55) : Traced the pathway of carbon ixation., , www.cleariitmedical.com

Page 57 :
Site for photosynthesis : Photosynthesis takes place only in green parts of, the plant, mostly in leaves. Within a leaf, photosynthesis occurs in mesophyll cells, which contain the chloroplasts. Chloroplasts are the actual sites for photosynthesis., The thylakoids in chloroplast contain most of pigments required for capturing solar, energy to initiate photosynthesis : The membrane system (grana) is responsible for, trapping the light energy and for the synthesis of ATP and NADPH. Biosynthetic, phase (dark reaction) is carried in stroma., (Refer igure 13.2, Page 209, NCERT Text Book of Biology, Class XI), Importance of Photosynthesis—(1) Synthesis of organic compounds (2), Change of radiant energy into chemical energy (3) Useful products are obtained, from plants gums, oils timber ire wood, resins rubber, ibers and drugs, etc. (4), Balance the percentage of O2 and CO2 in atmosphere (5) Fossil fuels like coal,, natural gas and petroleum have been formed inside the earth indirectly as a product, of photosynthesis., , Pigments involved in photosynthesis :, Chlorophyll a : (Bright or blue green in chromatograph). Major pigment,, act as reaction centre, involved in trapping and converting light into chemical, energy. It is called universal photo-synthetic pigment., Chlorophyll b : (Yellow green), Xahthophylls : (Yellow), Carotenoids : (Yellow to yellow-orange), , , In the blue and red regions of spectrum shows higher rate of photosynthesis., , Light Harvesting Complexes (LHC) : The light harvesting complexes are, made up of hundreds of pigment molecules bound to protein within the photosystem, I (PS-I) and photosystem II (PS-II). Each photosystem has all the pigments except, one molecule of chlorophyll ‘a’ forming a light harvesting system (antennae). The, reaction centre (chlorophyll a) is different in both the photosystems. (Refer ig., 13.4, Page 211, NCERT-Biology)., , www.cleariitmedical.com

Page 58 :
Light Harvesting Complex, Photosystem I (PS-I) : Chlorophyll ‘a’ has an absorption peak at 700 nm, (P700)., Photosystem II (PS-II) : Chlorophyll ‘a’ has absorption peak at 680 nm, (P680),, Process of photosynthesis : It includes two phases-Photochemical phase, and biosynthetic phase. (Formerly known as Light reaction and dark reaction), (i) Photochemical phase (Light reaction) : This phase includes-light, absorption, splitting of water, oxygen release and formation of ATP and NADPH., It occurs in grana region of chloroplast., (ii) Biosynthetic phase (Dark reaction) : It is light independent phase,, synthesis of food material (sugars). (Calvin cycle). It occurs in stroma region of, chloroplast., Photophosphorylation : The process of formation of high-energy chemicals, (ATP and NADPH) in presence of light., Non-Cyclic photophosphorylation : Two photosystems work in series–First, PSII and then PSI. These two photosystems are connected through an electron, transport chain (Z. Scheme). Both ATP and NADPH + H+ are synthesised by this, process. PSI and PSII are found in lamellae of grana, hence this process is carried, here. (Fig. 13.6) Page 213, NCERT-BIOLOGY. Class-XI., , www.cleariitmedical.com

Page 59 :
Cyclic photophosphorylation : Only PS-I works, the electron circulates, within the photosystem. It happens in the stroma lamellae (possible location), because in this region PSII and NADP reductase enzyme are absent. Hence only, ATP molecules are synthesised. It occurs when only light of wavelengths beyond, 680 nm are available for excitation., The electron transport (Z-Scheme) : In PS II, reaction centre (chlorophyll, a) absorbs 680 nm wavelength of red light which make the electrons to become, excited. These electrons are taken up by the electron acceptor that passes them to, an electron transport system (ETS) consisting of cytochromes. The movement of, electron is down hill. Then, the electron pass to PS I and move down hill further., (Fig. 13.5) Page 212, NCERT-BIOLOGY-Class XI, The splitting of water : It is linked to PS II. Water splits into H+, [O] and, electrons., 2H2O → 4H+ + O2 + 4e–, Chemiosmotic Hypothesis : Chemiosmotic hypothesis explain the, mechanism of ATP synthesis in chloroplast. In photosynthesis, ATP synthesis, is linked to development of a proton gradient across a membrane. The protons, are accumulated inside of membrane of thylakoids (in lumen). ATPase enzyme, has a channel of that allow diffusion of protons back across the membrane. This, release energy to activate ATPase enzyme that catalyses the formation of ATP., (Fig. 13.7). Page 214, , www.cleariitmedical.com

Page 61 :
6CO2 + 6PEP + 6RuBP + 30ATP + 12NADPH +12H+ Enzymes, C6H12O6 + 6PEP + 6RuBP + 30ADP + 12NADP+ + 3OH3PO4, Photorespiration : The light induced respiration in green plants is called, photorespiration. In C3 plants some O2 binds with RuBisCO and hence CO2 ixation, is decreased. In this process RuBP instead of being converted to 2 molecules of, PGA binds with O2 to form one molecule of PGA and phosphoglycerate., , There is neither synthesis of ATP nor NADPH2 or sugar. There is 25% loss, of ixed CO2 so it is wasteful process., , C4 Plants :, , (1) Lack Photorespiration, (2) Show response to high light intensities, (3) Have greater productivity of biomass., , Adaptations in C4 Plants :, (i) Kranz Anatomy, (ii) Occurrence of two types of cells, (iii) Dimorphic chloroplast, (iv) Presence of RuBisCO in Bundle Sheath cells and PEPase in mesophyll, cells., (v) Mechanism to increase CO2 concentration near RuBisCO in Bundle, Sheath cells., CAM (Crassulacean Acid Metabolism) Plants—Stomata open at night. e.g.,, Cacti, Bryophyllum, Pineapple., Law of Limiting Factors : If a chemical process is affected by more than, one factor, then its rate will be determined by the factor which is nearest to its, minimal value. It is the factor which directly affects the process if its quantity is, changed Factors affecting photosynthesis :, 1. Light : Rate of photo-synthesis increases at low light intensities. At high, intensities of light beyond a point the rate of CO2 ixation decreases. Longer, hours of light duration favour more photosynthesis rate., 2. Carbon dioxide : Increase in CO2 concentration causes increases in CO2, ixation. It is the major limiting factor for photosynthesis., 3. Temperature : The rate of photosynthesis at optimum temperature is, high., It is 20°C-25°C For C3 plants and 30-45°C for C4 plants., 136, , www.cleariitmedical.com

Page 63 :
Points To Remember, Aerobic respiration : Complete oxidation of organic food in presence of, oxygen thereby producing CO2, water and energy., Anaerobic respiration : Incomplete breakdown of organic food to liberate, energy in the absence of oxygen., ATP Synthetase : An enzyme complex that catalysis synthesis of ATP during, oxidative phosphorylation., Biological oxidation : Oxidation in a series of reaction inside a cell., Cytochromes : A group of iron containing compounds of electron transport, system present in inner wall of mitochondria., Dehydrogenase : Enzyme that catalyses removal of H atom from the, substrate., Electron acceptor : Organic compound which receive electrons produced, during oxidation-reduction reactions., Electron transport : Movement of electron from substrate to oxygen through, respiratory chain during respiration., Fermentation : Breakdown of organic substance that takes place in certain, microbe like yeast under anaerobic condition with the production of CO2 and, ethanol., Glycolysis : Enzymatic breakdown of glucose into pyruvic acid that occurs, in the cytoplasm., Oxidative phosphorylation : Process of formation of ATP from ADP and, Pi using the energy from proton gradient., Respriation : Biochemical oxidation food to release energy., Respiratory Quotient : The ratio of the volume of CO2 produced to the, volume of oxygen consumed., Proton gradient : Difference in proton concentration across the tissue, membrane., , www.cleariitmedical.com

Page 65 :
A. Glycolysis : The term has origianted from the Greek word, glycos =, glucose, lysis = splitting, or breakdown means breakdown of glucose molecule, to pyruvic acid. It was given by Embden Meyerhof and Parnas. It is a chainof, 10 reactions to convert glucose into pyruvate. It is common for acerobic and, anaerdomic respiration., , Steps for Glycolysis—(EMP Pathway), 1., , Phosphorylation of Glucose into Glucose-6-phosphate, 2., Isomerisation of Glucose-6-Phosphate into fractose-6-phosphate, 3., Second phosphorylation in which Fructose-6-phosphate changes into Fructose-1,, 6-biphosphate, 4., Splitting of Fructiose-1, 6-biphosphate into DiHAP and PGAL, 5., Isomerisation of DiHAP into PGAL, 6., Oxidation of PGAL into 1, 3-biphosphosphoglycerate, 7. Synthesis of ATP and converssion of 1, 3-biphosphoglycerate into 3-phospholycerate, 8., Isomerisation of 3-phosphoglycerate into 2-phospholycerate, 9., Dehydration of 2-phosphoglycerate into PEP, 10. Substrate level ATP synthesis and formation of Pyruvic Acid., , It is also called Embden—Meyerhof—Paranas pathway. (EMP pathway), It is common in both aerobic and anaerobic respiration., It takes palce outside the mitochondria, in the cytoplasm., One molecule of glucose (Hexose sugar) ultimately produces two molecules, of pyruvic acid through glycolysis.’, During this process 4 molecules of ATP are produced while 2 molecules, ATP are utilised. Thus net gain of ATP is of 2 molecules., , , , , , , , , Input and Output of glycolysis, S. No., , Input, , Output, , 1., , Glucose (6—C) —1, , Pyruvate (3—C) 2 molecules, , molecule, 2., , 2 ATP, , 2 ADP, , 3., , 4 ADP + 2 Pi, , 4 ADP + 2H2O, , 4., , 2 NAD+, , 2 NADH (H+), , Net out put ...... 2 Pyruvate + 2ATP + 2NADH (+ H+) OR 2 Pyruvate + 8 ATP, , The pyruvate, so produced, may under go (i) Lactic acid fermentation,, Alcoholic fermentation of Aerobic Respiration (Krebs Cycle), B. Oxidative decarboxylation : Pyruvic acid is converted into Acetyle CoA, in presence of pyruvate dehydrogenase complex., , www.cleariitmedical.com

Page 66 :
Pyruvic acid + CoA + NAD +, , Acetyle CoA + CO2 + NADH + H+, , The Acetyle CoA enters in TCA cycle., C. Tri Carboxylic Acid Cycle (Kereb’s cycle) or Citric acid Cycle : This, cycle starts with condensation of acetyle group with oxaloacitic acid and, water t o yield citric acid which under goes a series of reactions., , It is aerobic and takes a place in mitochondrial matrix., , Each pyruvic acid molecule produces 4 NADH + H+, one FADH2, one, ATP., , One glucose molecule has been broken down t o release CO2 and eight, molecules of NADH + H+, two molecules of FADH2 and 2 molecules, of ATP., Compensation Point : It is the value of a factor at which the rate of, photosynthesis controlled by it is just equal to the rate of respiration and, photorespiration so that there is not net exchcange of gases between the, phtosynthetic organ and the environment., At compensation point the photosynthetic tissue manufacture only such, amount of food which of suficient for it to remain alive. No food is supplied, to rest of the plant. Therefore, net photosynthesis is zero., (D) Oxidative Phosphorylation, The synthesis of ATP from ADP and inorganic phosphate using energy from, proton gradient is called oxidative phosphorylation. This takes place in, elementry particles present on the inner membrane of cristae of mitochondria., This process in mitochondria is catalysed by ATP synthestase (complex V)., This compmlex has two major components F0 and and F1, F0 acts a channel, for proton and F1 acts as an ATP synthetase., , Electron Transport System and Oxidative Phosphorylation, Name of Complex, Complex I, Complex II, Complex III, Complex IV, Complex V, , Components of ETS, FMN and Fe-S are prosthetic groups and NADH, dehydrogenase, FADH2 dehydrogenase (succinate dehydrogenase), Fe-S,, UQ, Cytochrome bc, complex–cytochrome b, cytochrome C,, Fe-S, UQ, Cytochrome Coxidase–Cytochrome a1, cytochrome a3 which, posses two copper centres., F0–F1 particles Flow of protein through F0 channel induces, F1 partcile to function as ATP synthatase., 145, , www.cleariitmedical.com

Page 68 :
Amphibolic Pathway :, During the process of cellular respiration Carbohydrates, fats and protiens, are broken down to release energy and hence respiration is a catabolic process/, catabolic pathway. From this pathway many compound are withdrawn for synthesis, of substrates. Some anabolic processes are formation of pyruvic acid from amino, acids, and formation of Acetyl CoA from Fatty acid. So—Respiratory pathway is, involved in both catabolism and anabolism, it is better to consider the respiratory, pathway as an amphibalic pathway., , RQ (Respiratory quotient), (a) RQ = 1 (When carbohydrate is used as substrate), C6H12O6 + 6O2 → 6CO2 + 6 H2O + Energy, (b) RQ is less than 1 (i.e., < 1) for fats., 2C51H98O6 + 145O2 → 102CO2 + 98 H2O + Energy, R.Q. ⇒, , = 0.7, , (c) RQ is 0.9 for proteins., (d) RQ is more than 1 (i.e., > 1) for organic acids., (e) RQ is iniinite in case of anerobic respiration, because CO2 is evolved but, O2 is not consumed., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 69 :
Points To Remember, Seed Germination : The seed germinates only when favourable conditions, for growth exists in the environment. In absence of favourable conditions it goes, into a period of suspended growth or rest, called dormancy., Abscission : Shedding of plant organs like leaves, lowers and fruits etc., from the mature plant., Apical dominance : Suppression of the growth of lateral buds in presence, of apical bud., Dormancy : A period of suspended activity and growth usually associated, with low metabolic rate. Some, seeds undergo a period of dormancy and can, germinate only after dormancy period gets over., Phytochrome : A pigment, found in plants which control the light dependent, developmental process., Phytohormone : Chemicals’ secreted by plants in minute quantities which, inluence the physiological activities., Sensecene : The last phase of growth when metabolic activities decrease., Vernalisation : A method of promoting lowering by exposing the young, plant to low temperature., Growth : An irreversible permanent increase in size, volume and weight of, an organ or its parts or even of an individual., Quiescence : Non germination of a viable seed due to non-availability of, proper environmental conditions., Vivipary : It is the germination of seed while it is still attached to the parent, plant and is nourished by it. e.g., Rhizophora and Sonneratia. As the germinating, seed forms a seedling. It all down into the mud due to increase in weights. In the, mud, lateral roots develops for anchorage., Heterophylly :Occurrence of more than one type of leaves in plants e.g.,, larkspur, Coriander leaves of Juvenile plant are different in shape from mature, plant., , www.cleariitmedical.com

Page 70 :
Bolting : Elongation of internodes prior to lowering in plants like Cabbage., Photoperiodism : Response of Plants to relative periods of day/night to, induce lowering., According to duration of exposure of plants to light, plants are divided in, 3 categories :, 1. Long Day Plants (LDP)—Plants which need exposure to light for period, exceeding critical duration e.g., wheat, rice, cucumber., 2. Short Day Plants (SDP)—Plants that need exposure to light for period less, than the critical length e.g., Cabbage., 3. Day Neutral Plants (DNP)—There is no correlation between exposure to, light duration & induction of lowering e.g., Tomato., Abbreviations, IAA, Indole acetic acid, NAA, Napththalene acetic acid, ABA, Abscisic acid, IBA, Indole-3 butyric acid, 2.4D, 2.4 dichlorophenoxy acetic acid, PGR, Plant growth regulator, Seed Dormancy, It is the condition of seed when it is, unable to germinate in spite of the, availability of all environmental conditions suitable for germination., , Quiescence, The condition of a seed when it is, unable to germinate because the, conditions for germination are not, available., , Measurement of growth : Plant growth can be measured by a variety of, ft parameters like increase in fresh weight, dry weight, length, area, volume and, cell number., Phases of growth : The period of growth is generally divided into three, phases, namely, meristematic, elongation and maturation., (i) Meristematic zone : New cell produced by mitotic division at root-tip and, shoot-tip thereby show increase in size. Cells are rich in protoplasm and, nuclei., (ii) Elongation zone : Zone of elongation lies just behind the meristematic zone, and concerned with enlargement of cells., , www.cleariitmedical.com

Page 71 :
(iii) Maturation zone : The portion lies proximal to the phase of elongation., The cells of this zone attain their maximum size in terms of wall thickning, and protoplasmic modiication., Growth rate : The increased growth per unit time is termed as growth rate., The growth rate shows an increase that may be arithmetic or geometrical., Growth, In Arithmetic growth :, , Mathematical expression, L1 = L0 + rt, , Curve, Linear curve, , Only one daughter cell continues L1 = Length at time t, to divide mitotically while other, differentiate and matures., , L0 = Length at time zero, r = growth rate, , Sigmoid Growth Curve, Geometrical growth, , Formula, , Shape of curve, , The initial growth is, , W1 = W0ert, , Sigmoid or, , slow (lag phase) and increase, , W0 = Initial size, , S-curve, , rapidly there-after at an, , W1 = Final Size, , exponential rate (log phase), , r = growth rate, , In both, the progeny cells divide, , t = time of growth, , mitotically and continue to do so. e = base of natural, However, with limited nutrient, supply, the growth slow down, leading to stationary phase., , www.cleariitmedical.com, , logarithms

Page 72 :
Sigmoid growth curve, Lag phase—Growth is slow in initial stage., Log phase : Period of maximum growth, Stationary phase—When the nutrients become limiting, growth slows down., Relative Growth : The growth per unit time as percentage of initial size, RGR =, , × 100, , Differentiation : A biochemical or morphological change in meristemic, cell (at root apex and shoot apex) to differentiate into permanent cell is called, differentiation., Dedifferentiation : The phenomenon of regeneration of permanent tissue, to become meristematic is called dedifferentiation., Redifferentiation : Meristems/tissue are able to produces new cells that, once again lose the capacity to divide but nature to perform speciic functions., , Conditions or factors influencing Growth, 1. Nutrition 2. Availability of water 3. Temperature 4. Oxygen 5. Light, 6. Gravity 7. Stress factors like minerals, water or temperature etc., Phytohormone or Plant Growth-Regulator, Growth promoting hormones : These are involved in growth promoting, activities such as cell division, cell enlargement, lowering, fruiting and seed, formation. e.g., Auxin, gibberellins, cytokinis., Growth inhibitor : Involved in growth inhibiting activities such as dormancy, and abscission. e.g., Abscisic acid and Ethylene., Hormones, 1. Auxins (Growth Promoters), e.g.Indole 3-Acetic Acid, [2, 4-D and 2, 4, 5,-T etc.], , Functions, 1. Apical dominance, cell elongation,, Promote lowering prevent premature, leaf and fruit falling, initiate rooting, in stem cutting, as weedicide, induce, parthenocarpy., , 2. Gibberellins (Growth Promoters) 2. Delay senescence, speed up malting, process, increase in length of axis,  GA 3 (C19 H 22 O6 , (grape stalk), increase in length of stem, eg. GA 4 , GA 7 , GA19 and , (sugarcane), bolting in beet, cabbages and, , , many plants with rosette habit., GA 20 etc., 154, , www.cleariitmedical.com

Page 73 :
3. Cytokinins (Growth Promoters), e.g.  Zeatin (trans 6-purine ,  DMAA-Dimethylalyl , , , adenine and Isopentyl , , , adenine (IP) etc., , 4. [Ethylene (H2C = CH), A goreous PGR which acts, as Growth Promoters as well, growth inhibitor (mainly as, growth inhibitor), 5. Abscisic acid (ABA), eg. (Abscisin II Dormin), , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org), , 3. Promote cell division, induce cell, enlargement, reduce apical dominance,, induce growth in auxiliary bud, chlorophyll, preservation, lateral shoot growth,, adventitious root formation., , 4. Promotes senescence and abscission of, leaf and fruits, promotes ripening of fruits,, break seed and bud domancy, initiate, germination in peanut, sprouting of potato, tuber, promotes root growth and root hair, formation., 5. Inhibit seed germination, stimulate closer, of stomata, increase tolerance to various, stress, induce dormancy in seed and bud,, promotes ageing of leaf (senescence)., Can delay the ripening of stored fruits as, it absorbs the ethylene.

Page 74 :
Points To Remember, Blood : A special connective tissue that circulates in principal vascular, system of man and other vertebrates consisting of fluid matrix, plasma and formed, elements (Blood = Plasma + All blood cells)., Plasma : (Blood – All blood cells = Plasma) The liquid part of blood which, is straw coloured, viscous fluid and contains about 90-92% of water and 6-8%, proteins., Lymph : A clear yellowish, slightly alkaline, coagulable tissue fluid,, containing white blood cells (Only lymphocytes), a liquid resembling blood, plasma., Serum : Blood plasma from which ibrinogen and other clotting factors, have been removed. (Plasma– (ibrinogen & other clotting factor) = blood serum., Heart Beat : The rhythmic contraction and relaxation of the heart, which, includes one systole (contraction phase) and one diastole (relaxation phase) of, the heart. Heart beat count of healthy person is 72 times per minute., Stroke Volume : The volume of blood pumped out by the heart during a, systole. If is approximately 70 ml., Cardiac output : The amount of blood pumped by heart per minute is called, cardiac or heart output. The value of cardiac output of a normal person is about, 72 × 70 = 5040 mL or about 5L per minutes., Cardiac Cycle : The rhythmic contraction and dilation of diferent parts of, heart in one beat., Systole : Contraction of heart muscles., Diastole : Relaxation of heart muscles, , www.cleariitmedical.com

Page 75 :
TYPES OF BLOOD CELLS THEIR NUMBER, STRUCTURE & FUNCTIONS, Name and Number/, Percentage, , Structure, , Life Span and, Formation, , Function, , (A) Erythrocytes RBCs, , Red colour, , Formed from birth, , Transport of oxygen, , - 4.5 to 5.5 million, , Circular, biconcave, , onward by red bone, , and some amount, , per cubic millimetre of, , denucleated, elatic, , marrow Life-120 days of carbon dioxide, , blood, , lack of cell organelles excess RBCs are, like ER, ribosomes,, , through haemoglobin, , tored in spleen, , mitochondria etc., (B) Leucocytes, , Colourless rounded, , Formed in red bone, , Acts as soldiers, , (WBCs) 5000-8000, , or irregular,, , marrow, Lymph, , scavenger and some, , per cubic mm of, , nucleated 12 to, , nodes, spleen and, , help in healing, , blood, , 20mm wide, life 1-4, , thymus, , days, (i) Agranulocytes, , Large rounded, , Lymph nodes,, , Non Phagocytic, , (a) Lymphocytes 20-45% nucleus, 6-10 mm, , spleen, thymus red, , secrete antibodies, , of leucocytes, , bone marrow, life few, days to months or, even years, , (b) Monocytes 6-8% of, leucocytes,, , Larget of all (12-15, , Red Bone marrow,, , mm) bean shaped, , life 10-20 hours, , nucleus, , phagocytic, very, motiles engulf, germs, , (ii) Granulocytes, (a) Eosinophils 2-3%, , bilobed nucleus,, , Red Bone marrow,, , of leucocytes, , granules in cytoplasm life 4 to 8 hrs. in, , play role in immunity, non phagocytic, , blood, (b) Basophils 0-5% of, , Three lobed nucleus, , Red Bone marrow,, , release heparin and, , leucocytes, , (s-shaped), , life 4 to 8 hours in, , hitamine, , blood, (c) Neutrophils 60-65%, , Many lobed nucleus, , Red Bone marrow,, , phogocytic, engulf, , of leucocytes, , ine granules, , life 4 to 8 hours in, , germ and dead cells, , blood, (C) Platelets, , Colourless, rounded, , Red Bone marrow, , thrombocytes, , or oval, or irregular, , worm out ones, , 1,50,000-3,50,000 per, , non-nucleated, , phagocytized in blood, , cubic mm of blood, , fragments, , www.cleariitmedical.com, , help in blood clotting

Page 76 :
Blood Pressure—The resitance ofered by the lumen of the artery to the, low of Blood., Hypertension : The condition when blood pressure is higher than normal, (120/80 mmHg), Electrocardiograph : (ECG) the machine used to record electrocardiogram., Electrocardiogram ECG : The print out of pattern of heart beat taken on, a graph paper from Electrocardiograph. (EGC machine), , Lymph, The colourless mobile luid connective tissue drains into the lymphatic, capillaries from the intercellular spaces. It is formed by squeezing of blood through, capillaries, within tissues. Its low is unidirectional i.e., from tissues to heart., Composition : It is composed of luid matrix, plasma having only lymphocytes, of white blood corpuscles or leucocytes., Functions : (i) It drains excess of tissue luid from extra cellular spaces, back into the blood., (ii) It contain lymphocytes and antibodies., (iii) It transport digested fats., , Blood Clotting :, , Coagulation of Blood :, Injured Tissue, Blood Platelets, Releases, Disintegrate, ↓, and release ↓, Thromboplatins, Platelet thromboplatin, Ca++ Proteins, Ca+ Proteins, , Prothrombin, , ↓ ↓, Thrombokinase, Inactivates heparin and, catalyses, Ca++, Thrombin, , Fibrinogen, (Fibrin + Blood cells, Biology Class - 11, , www.cleariitmedical.com, , ↓ Catalyses, Fibrin, Clot or Coagulum)

Page 77 :
Functions of Blood, Transport, of food, respiratory gases (O2 and CO2), hormones, metabolic, intermediates, waste products, supply of raw materials, regulation of water balance,, regulation of pH and body temperature, and provides immunity., , Blood Groups : Based on presence of Antigens and Antibodies in blood., Blood Antigen (on Anti body : (in Possible recipients, Group the Surface, plasma), having blood group, of R.B.Cs), , Possible donors Remarks, having blood, group, , A, , A, , Anti B, , A, AB, , O, A, , —, , B, , B, , Anti A, , B, AB, , O, B,, , —, , AB, , A and B, , None, , AB, , O, A, B, AB, , Universal, recipient, , O, , None, , Anti A and, Anti B, , O, A, B, AB, , O, , Universal, Donor, , Rh (Rhesus) Group :, Discovered by Landsteiner and Wiener in 1940 the antigen found on the, surface of RBCs. The presence of this antigen is termed as Rh-positive (Rh+) and, its absence as (Rh–). It plays a crucial role in childs birth born out of a marriage, between Rh– woman and Rh+ man, causing to produce anti Rh antibodies., →SAN (Sino-artrial node) : A patch of tissues present in the right upper, corner of the right atrium, acts are pacemaker due to having a unique property, of self exitation., →AVN (Atrio Ventricular Node) : A mass of tissues seen in the lower left, corner of the right atrium close to the atrio-ventricular septum. Fresh wave of, contraction generated here, passes over both the ventricles simultaneously along, the bundle of his., , 179, , www.cleariitmedical.com

Page 78 :
Human Heart, , Human Heart, , , , , , , , , , , , It is the mesodermally derived organ situated in thoracic cavity in between, the two lungs. Protected by a double membrane covering called Pericardium., Four chambers–two (left and right) atria, and two ventricels (left and right), Inner-artrial septum separates the two atria and inter ventricular septum, separates the two ventricles, while the atria and ventricles are separated by, atrioventricular septum., The valves between right atrium and right ventricle is tricuspid while between, left atrium and ventricle is bicuspid or mitral value., The opening of the right ventricle into the pulmonary artery and the opening, of left ventricle in to aorta are guarded by semilunar values., The valves allow the low of blood only in one direction, i.e., from atria to, ventricles and from ventricles to pulmonary artery or aorta., , Heart Valves, Tricuspid Valve : The valves formed of three muscular laps or cups, which, guard the opening between the right atrium and the right ventricle., Bicuspid Valve (Mitral Valve) : The valves which guard the opening, between the left atrium and the left ventricle, made up of two laps., , www.cleariitmedical.com

Page 79 :
Semilunar Valves : The valves present at the opening of the right and the, left ventricles and allow the entry of blood into pulmonary artery and the aorta, respectively., Standard ECG & Reading of ECG : ‘P’ Wave represents the electrical, excitation (or depolarisation) of the atria and leads to the contraction of both the, atria., Electrocardiogram ECG : The graphic record of the electric current, produced by the excitation of the cardiac muscles. It is composed of a ‘P’ wave,, ‘QRS’ wave. (complex) and ‘T’ wave (for a standard ECG) (Refer fig. 18.3, page, 286 (NCERT class XI Biology), , Diagrammatic presentation of a tandard ECG., , ‘QRS’ complex : represents the depolarisation of the ventricles, which, initiates the ventricular contraction., ‘T’ Wave : represents the return of the ventricles from excited to normal, state (repolarisation). The end of T-wave marks the end of sytole., , Double circulation :, The passage of same blood twice through heart in order to complete one, cycle. i.e. It is completed in following two steps., (i) Pulmonary Circulation : The blood pumped by the right ventricle, (deoxygenated blood) is transported through pulmonary artery to lungs where, CO2 is exchanged with O2 through diffusion and returns back to the heart, through pulmonary vein. It is called pulmonary circulation., (ii) Systemic Circulation : The oxygenated blood from left ventricle is, transported through aorta to different body parts (cells and tissues) where, O2 is exchanged with CO2 through diffusion and then returned back to the, heart through vena-cava. It is called systemic circulation., , Disorders of circulatory System, Hypertension (High blood Pressure) : It results from narrowing of arterial, lumen and reduced elasticity of arterial walls in old age. It can cause rupturing of, capillaries. It is a silent killer., , www.cleariitmedical.com

Page 80 :
Coronary Artery Disease : (CAD) Atherosclerosis. The supply of the blood, to heart muscles is affected. It is “caused by deposits of Calcium, fat, cholesterol, and fibrous tissues to make the lumen of arteries narrower., Angina Pectoris : Caused due to arteriosclerosis, when no enough oxygen, is reaching the heart muscle due to which the person experiences acute chest pain., Heart attack : Caused when the heart muscle is suddenly damaged by an, inadequate blood supply., Cardiac arrest : The state in which the heart stops beating., Arteriosclerosis : The state of hardening of arteries and arterioles due, to thickening of the fibrous tissue and consequent loss of elasticity. It causes, hypertension., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 81 :
Points To Remember, Ammonotelism :, The animals which excrete ammonia are called ammonotelic and excretion, of ammonia is known as ammonotelism eg. Amoeba, sycon, hydra, liver luke,, tapeworm, Leech, Prawn, bony ishes etc., , Ureotelism :, excretion of urea is known as ureotelism and the animals which excrete, urea are ureotelic animals eg. mammals, many terrertrial amphibians and marine, ishes and sting rays etc., , uricotelism :, Excretion of uric-acid is known as uricotelism and the animals are called, uricotelic eg. most insects, land snails, lizards, snakes and birds., , Nephrons :, The structural and functional unit of kidneys. Each kidney contains about, one million of nephrons., , Structure of Nephron :, A nephron consists of Glomerulus, Bowman’s capsule, PCT (Proximal, Convoluted Tubule). JG A (Juxaglomerular Apparatus), DCT (Distal Convoluted, Tubule) and the collecting duct. (Refer ig., 19.3, page 292 (NCERT Text Book, of Biology for Class XI), , Structure of Kidney :, Size 10-12 cm in length, 5-7 cm in width, 2-3 cm thick, average weight, about 120-170 g.,  The blood vessels, ureter and nerves enter in the kidney through hilum, (a notch)., , www.cleariitmedical.com

Page 82 :
, , The outer layer of kidney is a tough capsule., , , , The outer zone of kidney is cortex and the inner is medulla., , , , , , The medulla is divided into few conical masses (medullary pyramids), projecting into calyces., The cortex extends between medullary pyramids called columns of Bertini., Refer igure 19.2, page 292 (NCERT—Class XI Biology), , Glomerular Filtration :, The iltration of blood in glomerulus, about 1100-1200 ml of blood is iltered, by the kidney per minute., , Glomerular Filtration Rate (GFR) :, The amount of iltrate formed by the kidney per minute is called GFR. In a, healthy individual it is about, 125 ml/minute, i.e. 180 litres per day., , Types of Nephrons :, (i) Juxtamedullary Nephron—About 15% of total nephrons, Glomeruli are, found in inner region of cortex, large in size, long loop of Henle and found, deep in medulla, associated with vasa recta control plasma volume when, water supply is short., (ii) Cortical Nephron—About 85% of total nephron mainly lie in renal cortex,, glomeruli found in outer cortex, short loop of Henle, extends very little in, medulla. They do not have vasa recta or vasa recta is highly reduced., , Functions of Tubules :, (i) PCT—absorption of all essential nutrients and 70-80% of electrolytes and, water, helps to maintain the pH and ionic balance of body luids by selective, secretion of H+, ammonia and K+ into iltrate., (ii) Henele’s Loop—reabsorption in this segment is minimum, it plays a, signiicant role in maintenance of higher molarity of medullary intertitial, luid., (iii) DCT—conditional reabsorption of Na+ and water takes place here,, reabsorption of HCO3– and selective secretion of H+ and K+ and ammonia, to maintain the pH and sodium-potassium balance in blood., (iv) Collecting duct—Large amount of water is absorbed from this region to, produce concentrated urine, it plays a role in maintenance of pH and ionic, balance of blood by selective secretion of H+ and K+ ions., , www.cleariitmedical.com

Page 83 :
Steps of Urine Formation, 1. Gromerular Filtration—Blood is iltered by glomerulus through three, membranes i.e., endothelium of blood vessel, iltration slits of Bowman’s, capsule and basement membrance between these two layers. This iltration is, called ultrailtration as all constituents of plasma comes into ilterate except, proteins., 2. Reabsorption—90% of iltrate is reabsorbed by the renal tubules by active, or passive mechanism., It is evident by the fact that out of 180L of iltrate formed per day only 1.5, L of urine released., 3. Secretion—Tubular cells secrete H+, K+, ammonia into the urine. It maintains, acid-base balance of body luids., , Mechanism of concentration of the Filtrate (Countercurrent Mechanism) :, Refer ig 19.6 page 296 (NCERT-Class XI Biology), This mechanism is said to be countercurrent mechanism because the out, low (in the ascending limb) runs parallel to and in the opposite direction of, the inlow (in the descending limb).,  NaCl is transported by the ascending limb of Henle’s loop which is exchanged, with the descending limb of vasa-recta.,  NaCl is returned to the interstitium by the ascending portion of vasa recta.,  Henle’s loop and vasarecta as well as the counter current in them help to, maintain an increasing osmolality towards the inner medullary interstitium, i.e., from 300 mosmol/L in cortex to about 1200 mosmol/L in inner medulla.,  Small amount of urea enter, the thin segment of ascending limb of Henle’s, loop which is transported back to the interstitium by the collecting tubule.,  This mechanism helps to maintain a concentration gradient in the medullary, tubule interstitium.,  It helps in an easy passage of water from the collecting tubule to concentrate, the iltrate i.e. urine., Anti Diuretic Hormone (ADH) Controls the urine formation when there, is less blood volume due to excessive loss of luid from the body, osmoreceptors, send the signal to hypothalamus to release ADH which in turn facilitates water, reabsorption thus preventing diuresis (increase in frequency of urination), , , www.cleariitmedical.com

Page 84 :
Micturition :, The expulsion of urine from the urinary bladder is called micturition. It is, a relex process but can be controlled voluntarily up to some extent in grown up, children and adults.,  The CNS (Central Nervous System) sends the signal which cause the, stretching of the urinary bladder when it gets illed with urine.,  In response, the stretch receptors on the walls of the bladder sends signals, to the CNS.,  The CNS passes on motor message to initiate the contraction of smooth, muscles of the bladder and simultaneous relaxation of the urethral sphincter, causing the release of urine.,  An adult human excretes on an average 1 to 1.5 Litres res of urine per day.,  On an average 25-30 gram of urea is excreted out per day., , Renin Angiotensin System, Fall in GFR, ↓ Renin from JG cells, Angiotensinogen → Angiotensin I → Angiotensin II, ↓ Acts on, Adrenal Cortex, ↓ Secretes aldosterone, Reabsorption from DCT, ↓, Increase in GFR, , Role of other organs in excretion :, , , , , , , , Lungs—removes CO2 (18L/day) and water., Liver—secretes bilirubin, biliverdin etc. helps to eliminate these substances, along. with cholesterol, vitamins, drugs and degraded steroid hormones, through digesive wastes., Sweat and sebaceous glands—These glands of skin help to eliminate small, amount of urea, NaCl and lactic acid etc. through sweat while sebaceous, glands help to eliminate some substances like steroids, hydrocarbons and, waxes through sebum., Saliva—It can help to eliminate small amount of nitrogenous wastes., , www.cleariitmedical.com

Page 85 :
Disorders of Excretory system :,  Uremia—The accumulation of urea in blood due to malfunctioning of kidney., Hemodialysis—The process; of removal of urea from the blood artificially., In this process the blood from an artery is passed into dialysing unit after, adding an anticoagulant like heparin. The blood passes through coiled, cellophane tube surrounding by dialysing fluid. The nitrogenous wastes, from the concentration gradient and the blood becomes clear. This blood is, pumped back to the body through vein after adding anti-heparin to it.,  Renal calculi—The format ion of insoluble mass of crystallised salts (oxalates, or phosphates of calcium.,  Glomerulonephritis—Inlamation of glomeruli of kindney., , Kidney Transplantation,  Kidney transplantation is done in a patient in which both the kidneys fail to work i.e., at total failure of kidney. Kidney transplantation is the ultimate method for treatment, of renal failure. In case of kidney transplantation both the damaged kidneys of patient, are removed by surgery. And a functional kidney from a healthy donar preferably, from close relative is taken and transplanted in the body of patient. After successful, transplantation the patient and donar can survive on one kidney., Precautions taken for successful transplantation of Kidney :, 1. Kidney should be taken from a healthy donor preferably from close relative., 2. Matching of blood group and other factor and compatibility should be done, carefully before transplantation., 3. The patient (recipient) has to take some prescribed medicines, immunosuppresses through out the life to suppress the immune system., , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 86 :
Points To Remember, Coordination : Process through which two or more organs interact and, complement the functions of one another surrounding the brain., Action potential : A sudden change in the electrical charges in the plasma, membrane of a nerve ibre., Aqueous humour : The thin watery luid that occupy space between lens, and cornea in eye., Blind spot : A spot on ratina which is free from rods and cones and lack, the ability for vision., Cerebrospinal luid : An alkaline luid present in between inner two layer, of meninges, surrounding the brain and spinal cord., Cerebellum : A part of hind brain that controls the balance and posture of, the body., Cochlea : A spirally coiled part of internal ear which is responsible for, hearing., Corpus callosum : A curved thick bundle of nerve ibres that joins two, cerebral hemisphere., Depolarisation : A condition when polarity of the plasma membrane of, nerve ibre is reversed., Endolymph : The luid illed within membranous labyrinth., Ecustachian tube : A tube which connect ear cavity with the pharynx., Fovea : An area of highest vision on the ratina which contain only cones., Meninges : Three sheets of covering of connective tissue wrapping the brain., Grey Matter : This shows many convolutions which increase the amount, of vital nerve tissue., Medula oblongata : Posterior most part of the brain which is continuous, with spinal cord and control respiration, heart rate,swallowing,vomiting., , www.cleariitmedical.com

Page 87 :
Pons : Thick bundles of ibres on the ventral side of brain below cerebellum., Foramen magnum : A big aperture in the skull posteriorly through which, spinal cord emerges out., Spinal cord : A tubular structure connected with medulla oblongata of brain, and situated in the neural canal of the vertebral column, covered by meninges., Synaptic cleft : A narrow luid illed space which separates two membranes, of the two neurons at the synapse., Synaptic vesicles : These are membrane bound vesicles in the axoplasm of, the axon terminal and these store neurotransmitter., Neurotransmitter : These are chemicals stored in synaptic vesicles, diffuse, to reach the membrane of next neuron for its stimulation., Synapse : A physiological junction between axon of one neuron and dendrite, of next neuron., CNS—Central neural system, PNS—Peripheral neural system, ANS—Autonomic neural system, Neural System, Central neural System, Brain, , Peripheral neural System, , Spinal cord, , Cranial nerve, , Spinal nerve, , 12 pairs, , 31 pairs, , Nerve ibres of PNS, Afferent ibres Tansmit impulse, from Tissue/organ to CNS, , Efferent ibres Transmit impulse, from CNS to Peripherel tissue/organ, , Division of PNS, Somatic neural System, , Automatic neural system Transmit, , Relays impulse from CNS, , impulse from CNS to involuntary, , to Skeletal muscle, , www.cleariitmedical.com, , Organ and smooth muslces

Page 88 :
Cell body = Cytoplasm with nucleus, cell organelles and, Nissl’s granules, Parts of Neuron, , Dendrites = Short ibres which branch rapidly and project, out of cell, Axon =, , Single, long ibre, branched at distal endit, , (Refer ig. 21.1, page 317, NCERT - Biology, Class-XI), Multipolar = : One axon and two or more dentrites, : Found in cerebral Cortex, Neuron, , Bipolar =, , : One axon and one dendrite, : Found in ratina of eye, , Unipolar = : Cell body with axon only, : Found usually in the embryonic stage, Conduction of nerve impulse along axon, , Polarised membrane/Resting Potential, In resting phase when neuron is not conducting an impulse, the axonal, membrane is called polarised. This is due to difference in concentration of ions, across the axonal membrane., , At Rest :, , , Axoplasm inside the axon contain high conc. of K+ and low conc. of Na+., , , , The luid outside the axon contain low conc. of K+ and high conc. of Na+., , As a result the outer surface of axonal membrane is positively charged and, inner surface is negatively charged. The electric potential difference across the, resting plasma membrane is called resting potential., Action Potential : When a nerve ibre is stimulated, the permeability of, membrane to Na+ is greatly increased at the point of stimulus (rapid inlux of, Na+) and hence polarity of membrane is reversed and now membrane is said to, be depolarised. The electric potential difference across the plasma membrane at, that site is called action potential, which infact termed as nerve impulse., Depolarisation is very rapid, so that conduction of nerve impulse along the, entire length of axon occurs in fractions of second., , www.cleariitmedical.com

Page 89 :
Transmission of Impulses at Synapse, (i) At electrical synapses : Here the membrane of pre and post-syneptic neuron, are in very close proximity. Electric current can low directly from one neuron, into other across these synapses, like impule conduction along a single axon., (ii) At chemical synapses : Here the membrane of pre and post-syneptic neuron, are separated by luid illed space called synaptic cleft. Neurotransmitter are, involved here., When an impulse arrives at the axon terminal, it stimulates the movement of, the synaptic vesicles towards membrane and they fuse with the plsama membrane, and release their neurotransmitter in the syneptic cleft. These chemicals bind to, speciic receptors, present on the post-syneptic membrane. Their binding opens, ion channels and allow the entry of ion which generate new potential in post, synaptic neuron., Human brain : Human brain is the major portion of central neural system., Which is well protected by the skull., The brain is surrounded by three cranial meninges—, (i) Duramater—outer alyer, (ii) Arachnoid—middle layer, (iii) Piamter—Inner layer-remain incontact with brain, Parts of Brain, Fore brain, (a) Cerebrum, (b) Thalamus, (c) Hypothalamus, , Mid brain, , Hind brain, (a) Cerebellum, (b) Pons, (c) Medulla oblongata, , Functions of pars of brain :, Cerebrum : Centre of intelligence, memory and imagination, reasoning,, judgement, expression of will power., Thalamus : Acts as relay centre to receive and transmit general sensation, of pain, touch and temperature., Hypothalamus : Centre for regulation of body temperature, urge for eating, and drinking., Midbrain : Responsible to coordinate visual relexes and auditory relexes., Cerebellum : Maintains posture and equilibrium of the body as well as, coordinates and regulates voluntary movement., 207, , www.cleariitmedical.com

Page 90 :
Pons : Relays impulses between medulla oblongata and cerebral hemisphere, and between the hemisphere of cerebrum and cerebellum. It also heps to regulate, breathing., Medulla oblongata : Centre that control heart beat, breathing, swallowing,, salivation, sneezing, vomitting and coughing., Relex action : It is spontaneous, autonomic and mechanical response to, a stimulus that occurs at the level of spinal cord, without involvement of brain., Relex arc : The low of nerve along the speciic during relex action. It, consist of—, (a) A receptor, (b) An Afferent neuron (sensory neuron), (c) An inter neuron, (d) An efferent neuron (motor neuron), (e) An effector organ, Sensory neuron, Stimulus, Receptor, (REFLEX - ARC), Inter neuron of spinal cord, Response, Effector organ, motor neuron, Organ of Sight-Eye, Layer, , Component, , Function, , 1. External layer, , Sclera, , Protects and maintain shape of the, eye ball, , Cornea, , Outermost transparent portion of, eye which allows light to enter, , 2. Middle layer, , Choroid, , Absorb light and prevent light from, being relected within the eye ball., , 3. Inner layer, , Ciliary body, , Holds lens, regulate shape of the, lens., , Iris, , Control amount of light entering., , Retina, , Vision in dim light, colour vision,, vision in bright light. Sends the, image to brain through optical, nerves., , (Refer-Fig. 21.6, Page 323 NCERT-Biology, Class XI), 208, , www.cleariitmedical.com

Page 91 :
Organ of Hearing–Ear, Portion of the ear Component, 1. External ear, Pinna, External, auditory canal, , Function, Collect sound waves, Direct sound waves towards ear drum,, ear wax prevents the entry of foreign, bodies., 2. Middle ear, Tympanic, Acts as resonator that reproduces, membrane, the vibration of sound., Ear ossicles, Transmit sound waves to internal ear., Eustachian tube Helps in equalising the pressure, on either side of ear drum., 3. Internal ear, Cochlea, Hearing organ., Vestebular, Balancing of body., apparatus, (Refer Fig. 21.7, page 325-NCERT-Biology, Class XI), , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 92 :
Points To Remember, Endocrine glands : These are ductless glands which secrete hormones, directly into the blood stream., Hormones : Non-nutrient chemicals synthesised in trace amount by, Endocrine glands that act as intracellular messengers and are speciic in their, action which are transported by blood from site of production to site of action., , Hypothalamus :, , , , , , It is basal part of diencephalon., Has neurosecretory cells called nuclei which produce hormones to regulate, the synthesis and secretion of pituitary gland hormones., Two types of hormones released are :, Releasing hormones : Simulate secretion of pituitary hormones, e.g.,, Gonadotrophin releasing hormone stimulates pituitary gland to synthesise, gonadotrophins., Inhibiting hormones : Inhibit secretions of pituitary hormones, e.g.,, Somatostatin inhibits secretion of growth hormone., , Pituitary Gland :, , , Located in bony cavity called as sella tursica., , , , Attached to hypothalamus by a stalk., , , , , , , , Divided anatomically into : Adenohypophysis (Anterior lobe) and, Neurohypophysis (Posterior lobe)., Hormones released from hypothalamic neurons reach anterior pituitary, through portal system and through neurons in Posterior pitutary., Posterior pituitary is under neural control of hypothalamus., , www.cleariitmedical.com

Page 93 :
1. Pituitary Gland, Pituitary Gland, Adenohypophysis (Anterior lobe), , Neurohypophysis (Posterior lobe), (It stores hormones sureated by hypothalamus, , Pars distalis, , Pars intermedia, , Secretes, GH, , PRL, , Pars nervosa, , MSH, TSH, , ACTH, , LH, , FSH, , Oxytocin Vasopressin, (ADH), , Adenohypophysis :, Growth hormone (GH) : Oversecretion leads to gigantism and low secretion, causes dwarism and Proper reaction leads to proper growth of body.,  Prolactin (PRL) : Growth of mammary gland and formation of milk in, them.,  Thyroid stimulating hormone (TSH) : Stimulates synthesis and secretion, of thyroid hormones from thyroid gland.,  Adrenocorticotrophic hormone (ACTH) : Stimulates synthesis and, secretion of steroid hormones called glucocorticoids from adrenal cortex.,  Luteinizing hormone (LH) : Synthesis and secretion of hormones called, androgens in males, and helps in ovulation and maintenance of corpus luteum, in females.,  Follicle stimulating hormone (FSH) : Regulate spermatogenesis in males,, and growth and development of ovarian follicles in females.,  Oxytocin helps in contraction of uterus during child birth and milk ejection, from mammary gland in females.,  Vasopressin : Acts on kidney and stimulates reabsorption of water and, electrolytes by distal tubules to reduce water loss through urine. It is also, called as Anti Diuretic Hormone (ADH).,  Acrommegaly : It is a condition when the pituitary gland makes too much, growth hormone. It is due to a tumour in pituitary gland. Person suffering, from acromegaly (acro means tip and megaly means enlargement) may, gradually develop a long face with protruding lower law, enlarged nose and, wider spacing between teeth and enlarged hands and feet., 2. Pineal Gland :,  Located on dorsal side of forebrain., , , www.cleariitmedical.com

Page 94 :
, , 3., , , , , , , , , , , , , , , 4., , , , , , , 5., , , , , , , 6., , , , Secretes Melatonin to regulation 24-hours rhythm, sleep-wake cycle,, menstrual cycle, pigmentation etc., Thyroid Gland :, Has two lobes on either side of trachea interconnected by isthmus (connective, tissue)., Composed of follicles and stromal tissues., Follicular cells synthesis thyroxine (T4) and tri-iodothyronine (T3)., Iodine is necessary for normal functioning in of thyroid., Goitre (Hypothyroidism) : Enlargement of thyroid gland; Hypothyroidism, may lead to mental retardation and stunted growth (cretinism) Deaf-mutism, in the baby if it occurs during pregnancy., Hyperthyroidism : Occurs due to cancer or due to development of nodules, in thyroid glands. Effects body physiology as abnormal high levels of thyroid, hormones is synthesised. Basic metabolic rate increase., Exophthalmic goitre : It is a form of hyperthyroidism, characterised by, enlargement of thyroid gland, protrusion of eye balls and increased BMR, Thyroid hormone controls protein, carbohydrate metabolism., Also secretes a protein hormone called Thyrocalcitonin (TCT) which regulates, blood calcium level., Parathyroid Gland :, Present on back side of thyroid gland. Each lobe of thyroid gland has its one, pair., Secrete peptide hormone called parathyroid hormone (PTH) which increases, calcium levels in blood so called hypercalcemic hormone., PTH stimulates bone resorption, and reabsorption of calcium from blood and, reabsorption of calcium by renal tubules, thus increasing blood Ca++ level., Thymus Gland, Located on dorsal side of heart and aorta., Secrete peptide hormones called Thymosins which play role in differentiation, of T-lymphocytes (help in cell mediated immunity.), Thymosins also produce antibodies and provide humoral immunity., Immunity of old people usually becomes weak as thymus gets degenerated, with age., Adrenal Gland, Located at anterior part of each kidney., Has centrally located adrenal medulla and at periphery in adrenal cortex., , www.cleariitmedical.com

Page 95 :
, , , , , , , , Adrenal medulla secretes adrenaline (epinephrine) and nor adrenaline, (norepinephrine), commonly called as catecholamines or emergency, hormones or hormones of ight or light., These hormones increase heart beat, rate of respiration, breakdown of, glycogen thus increase blood glucose level, breakdown of lipids and protein,, alertness, raising of hairs, sweating etc., Adrenal Cortex-(3 layers) :, Zona reticularis (inner layer), Zona fasciculata (middle layer), Zona glomerulosa (outer layer), Adrenal cortex secretes :, , 1. Androgenic steroids :, , , Secreted in small amounts., , , , Play role in growth of axial pubic and facial hair during puberty., , 2. Glucocorticoids :, , , Involved in carbohydrate metabolism., , , , Stimulates gluconeogenesis, lipolysis and proteolysis., , , , e.g., Cortisol which is also involved in cardio-vascular and kidney functions., , , , It also suppresses immune response and stimulates RBC production., , 3. Mineralocorticoids :, , , , , , , , Regulate balance of water and electrolytes in body., e.g., Aldosterone which also helps in reabsorption of NA+ and water excretion, of K+ and phosphates ions from renal tubules., When adrenal cartex is damaged, it does not produce enough cortisols (which, regulate body’s reaction to stressful situations) and aldosterone., It result in Addison’s disease. Symptons of addison’s disease are weak, muscles, extreme fatigue, increased skin pigmentation, weight loss, sores, in mouth and depression., , Two major causes :, 1. Primary adrenal insuficiency where our immunity system mistakes adrenal, for an antigen and tries to damage it., 2. Secondary adrenal insuficiency-when pituitary gland can’t produce ACTH, , www.cleariitmedical.com

Page 96 :
7. Pancreas : It is called composite/dual gland. As it acts as Exocrine and, endocrine gland i.e. has both exocrine and endocrine function.,  Contains about 1-2 million islets of Langerhans which has glucagon secreting, α-cells and insulin secreting β-cell.,  Glucagon : Peptide hormone, stimulates glycogenolysis by acting on, liver cells. Also, stimulates gluconeogenesis. Hence called hyperglycemic, hormone.,  Insulin : Peptide hormone, acts on hepatocytes and adipocytes to enhance, cellular glucose uptake, stimulates conversion of glucose to glycogen, (glycogenesis), so decrease blood glucose level called hypoglycemic, hormone.,  Deiciency of insulin causes diabetes mellitus in which loss of glucose occurs, through urine. Excessive hunger and thirst (polydipsia) are other symptoms, of Diabetes.,  Insulin and glucagon are antagonistic hormones i.e. play apposite role., Glycogenolysis : Breaking of glycogen into glucose., Gluconeogenesis : Formation of glucose from substances other than glycogen., Glycogenesis : Conversion of glucose into glycogen., 8. Testis :,  A pair of testis composed of seminiferous tubules and interstilial cells is, present in the scrotal sac of males.,  Leydig cells (interstitial cells) produce androgens (mainly testosterone) which, regulate development and maturation of male accessory sex organs, formation, of secondary sex characters and play stimulatory role in spermatogenesis., Male sexual behaviour (libido) is inluenced by androgens., Ovary : A pair of ovaries which produce one ovum in each menstrual cycle are, present in abdomen in females.,  Ovary composed of ovarian follicles and stromal tissue.,  Estrogen synthesised by growing ovarian follicles helps in stimulation of, growth of female secondary sex organs, female behaviour, mammary gland, development and female secondary sex characters., , www.cleariitmedical.com

Page 97 :
, , Ruptured follicle form corpus luteum which secretes progesterone., Progesterone supports pregnancy and stimulates alveoli formation and milk, secretion in mammory glands., , Hormones secreted by tissues which are not endocrine, glands :, (a) Heart : Atrial wall secrets Atrial Natriuretic factor (ANF) which decreases, blood pressure by dilation of the blood vessels., (b) Kidney : Juxtaglomerular cells secretes erythropoietin which stimulates, erythropoiesis (RBC formation)., (c) Gastro-intestinal tract : it secrets four peptide hormones., , , , , , Gastrin : Acts on gastric glands and stimulates secretion of hydrochloric, acid and pepsinogen., Secretin : Acts on pancreas and stimulates secretion of water and bicarbonation., Cholecystokinin (CCK) : Act on pancreas and gall bladder to stimulate, secretion of pancreatic juice and bile juice respectively., , Gastric inhibitory peptide (GIP) : Inhibits gastric secretion and motility., Mechanism of hormone action : By hormone receptors of two kinds, i.e.,, (a) Located on membrane of target cell,  These are membrane bound receptors.,  From hormone receptor complex., ↓, Leads to biochemical changes in tissue., ↓, Release of second messengers like (cyclic AMP, IP3, Ca2+ etc.) which regulate, cellular metabolism., (b) Located inside the target cell,  These are intra cellular receptors.,  Hormones (steroid hormones iodothyronines etc.) interact with them and, cause physiological and developmental effects of regulating gene expression., , 218, , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org)

Page 98 :
Points To Remember, Arthritis : an inlammatory joint disease characterised by inlammation of, joints., Coccyx : tail bone formed by fusion of four coccygeal vertebrae in man., Dicondylic Skull : A Skull with two occipital condyles., Endo Skeleton : A skeleton present in side the body., Fascicle : Bundles of muscles ibres held together by connective tissue., Fascia : Collagenous connective tissue layer that surrounds muscle bundles., Floating ribs : The ribs that remain free anteriorly, (last 2 pairs), False ribs : 8th, 9th and 10th pair of ribs not directly joins the sternum but, to seventh pair of ribs, hence called pseudoribs., Myoglobin : A red colored pigment present in sarcoplasm of muscle., Sarcomere : A portion of myoibril between two successive ‘Z’ lines., Sarcocolema : The plasma membrane of a muscle., Gout : Inlammation of joints due to accumulation of uric acid crystal., Suture : immovable joints between skull bones., Synovial joints : Freely movable joints between limb bones., Patella : A seasmoid bone acting as kneecap., Intervertebral disc : Fibro cartilaginous pad present between the vertebrae, that act as shock absorbers., Tendon—Connective tissue made of yellow ibrous tissue which connect, muscle to bone. It is not lexible., Ligament—Connective tissue made of white ibrous tissue which joins two, bones. It is lexible., L.M.M. : Light meromyosin, HMM : Heavy meromyosin, Types of Movement :, , www.cleariitmedical.com

Page 99 :
1. Amoeboid movement : These movements takes place in phagocytes, where leucocytes and macrophages migrate through tissue. It is affected by, pseudepodia formed by the streaming of protoplasm (as in amoeba), 2. Ciliary movement : These movement occurs in internal organs which are, lined by ciliary epithelium., 3. Muscular Movement : This movements involve the muscle ibers, which, have the ability to contract and relex., Properties of Muscle : (i) Excitability, (ii) Contractility, (iii) Extensibility, (iv) Elasticity, , Types of Muscles :, (a) Skeletal muscles or striated muscles—These involved in locomotion and, change of body postures. These are also known as voluntary muscles., (b) Visceral muscles or smooth muscles—These are located in inner wall of, hollow visceral organ, smooth in appearance and their activity are not under, control of voluntary nervous system. They are called involuntary muscles., (c) Cardiac muscles—The muscles of heart, involuntary in nature, striated and, branched, These are uninucleated., Characteristic Skeletal Muscle, Location, Appearance, , Control, , Muscles attached with, skeletal components, Striated having light and, dark bands., They are controlled by, our will hence called, voluntary muscles., , Smooth Muscle, , Cardiac Muscle, , muscles found in the inner walls of hollow visceral organs, unstriped, smooth in, appearance with tapering, ends., They are not under the, control of our will hence, called involuntary muscles., , Muscles found only, in heart., Striated in, appearance and, branched, not under the, direct control of, nervous system., , Structure of myofibril :, , , , , , , , , , Each myoibril consist of alternate dark and light band., Dark band—contain myosin protein and is called A-band or Anisotroic band., Light band—Contain actin protein and is called I Band or Isotropic band., I Band is bisected by an elastic iber called ‘Z’ line. Actin ilament (thin, ilament) are irmly attached to the ‘Z’ lines., Myosin ilament (thick ilament) in the ‘A’ Band are also held together in, the middle of T Band by thin ibrous membrane called ‘M’ line., The portion between two successive ‘Z’ lines is considered as functional, unit of contraction and is called a sarcomere., , www.cleariitmedical.com

Page 100 :
Structure of Actin and Myosin Filament, I-Band, , Thin, ilament, Thick, ilament, , 1. Actin ilament : An actin ilament is made of two ‘F’ actins which are, helically wound to each other. Two ilaments of tropo myosin protein also, run close to ‘F’ actins throughout its length. A complex protein Troponin is, distributed at regular intervals on tropomyosin which mask the actin binding, site for myosin., 2. Myosin ilament : Each myosin ilament is a polymer of meromyosin., Each meromyosin has two components—a globular head with a short arm, and a tail. Head is made of heavy meromyosin while tail is made of light, meromyosin. The head with its short arm project outward at regular distance, and angle from each other and is known as cross arm. The head has an active, site for actin and binding site for ATP., , Red muscle fibres :, —, —, —, —, , These are red in colour due to presence of high content of myoglobin., These contain plenty of mitochondria., Sarcoplasmic reticulum is less in these ibres., Show slow but sustained contractions for longer periods., , www.cleariitmedical.com

Page 101 :
White muscle fibres, — These are pale or whitish due to presence of less content of myoglobin., — These contain fewer mitochondria, — Sarcoplasmic reticulum is more/high, — During strenuous exercise, lactic acid accumulates in large quantity so muscle, fatigues, , Mechanism or Muscle contraction : Sliding filament theory, The contraction of muscle iber takes place by the sliding of actin (thin, ilament) on myosin (thick ilament), , , Muscle contraction is initiated by a signal sent by the CNS via a motor, neuron., , , , Impulse from motor nerve stimulates a muscle iber at neuro muscular, junctions., , , , Neurotransmitter releases here which generates an action potential in, sarcolema., , , , This causes release of Ca++ into sarcoplasm. These Ca++ binds with troponin,, thereby remove masking of active site., , , , Myosin head binds to exposed active site on actin to form a cross bridge,, utilising energy from ATP hydrolysis., , , , This pulls the acin ilament towards the centre of ‘A’ band., , , , ‘Z’ lines also pulled inward thereby causing a shortening of sarcomere i.e., contraction., , , , I band get reduced, whereas the ‘A’ band retain the length., , , , During relexation, the cross bridge between the actin and myosin break., Ca++ pumped back to sarcoplasmic cisternae. Actin ilament slide out of ‘A, band and length of I band increase. This returns the muscle to its original, state., 199, , www.cleariitmedical.com

Page 102 :
Vertebral formulae of man C7T12L5S(5) C(4) = 33, Human skeleton – 206 bones, Axial skeleton (80 bones), , skull (29 bones), cranium-8 face-14, Ear ossicle-6, Hyoid-1, , Appendicular, skeleton (126 bones), , vertebrae (26) (33), 1, Cervical-7, stemum, Ribs, Thoracic-12, 1, 12 pairs (24), Lumber-5, sacral-1 (5-fused to form 1 sacrum), Caudal-1 (4-coccygeal fused to form 1 coccyx), , Girdles (6 bones), Pectoral (Shoulder girdle), Pelvic (Hip gridle( (2), , Clavicle 2, Scapula-2, , Fore limbs (60 bones) - 30 in each limb, Humerus-2, Radius-2, Ulna-2, Carplas-16, Meta Carpals-10, Phalanges-28=2× (2, 3, 3, 3, 3), , Cartilaginous joints, allo very slight, movement, , e.g., joints between, the bones of skull, , e.g., joint between, adjacent vertebrae, , 200, , www.cleariitmedical.com, Powered by TCPDF (www.tcpdf.org), , Joints, , Fibrous joints, do not allow, movement, , Ball and socket, Hinge, Joints, Joints, e.g., between humerus e.g., knee, and pectroal girdle, Joint, between femur, Elbow joint, and pelvic girdle, , Limbs (120 bones), , Pivot, Joints, e.g., Atlas, and axis, , Hind limbs (60) 30 in each limb, Femur-2, Tibia-2, Fibula-2, Patella-2, Tarsals-14, Meta Tarsal-10, Phalanges-28, , Synovial joints, Freely, movable, , Gliding, Joints, e.g., between, carpals, , Saddle, Joints, e.g., between, Carpals and meta, carpals of thumb