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Five marks questions, ‘ite the diagrammatic representation of life cycle of HIV., , —— ~, , Virus infects., normal cell, , , , , , Animal cell, Viral RNA is introduced into cell, , Cytoplasm, , produced, by reverse, transcriptase, , Viral DNA incorporates, into host genome, , uy), New viral RNA <, ia produced by Ga a, 5 Seek, , New viruses, are produced, , ) New viruses, Y) can infect other cells, , , , Viral DNA is |, , , , , Nucleus DNA, , , , , N NOTE: Infected clican survive white viruses are being ——_/, ee eieeaastaase, , (I-15), , 155, , , , Name the diseases caused by following organisms:, Rhino virus (b) Epidermophyton (c) Salmonella typhi (d) Wuchereria, malayi (e) Plasmodium vivax, , (a) Rhino virus ; Common cold., , (b) Epidermophyton : Ringworms, , (c) Salmonella typhi: Typhoid, , (d) Wuchereria malayi_ + Elephantiasis or filariasis, , (e) Plasmodium vivax : Malaria, , , , , , , (M-17), , 147/149, , , , , , A) Mention the four barriers of innate immunity with an example, for each. (4M), B) What is allergy? (1M), A) (i) Physical barriers : Example: Skin / Mucus, (ii) Physiological barrier: ample: Acid in the stomach / saliva in the, mouth / tears from eyes, (iii) Cellular barriers : Example: Polymorpho-nuclear leukocytes (PMNLneutrophils) / monocytes / natural killer cells (type, of lymphocytes), (iv) Cytokine barriers : Example: Interferons, , , , , , B) The exaggerated response of the immune system to certain antigens, present in the environment is called allergy., , , , (J-19), , , , 150/153, , , , Page 47