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Lesson 15. Water, , Multiple Choice Questions (MCQs). Tick (W) the correct options. Page No. 180, 1. (a) 2. (a) 3. (d) 4. (d) 5. (a), , LTD, , Multiple Choice Questions (MCQs). Tick (/) the correct options. Page No. 182, 1. (a) 2. (a) 3. (a) 4. (b) 5. (d), SECTIONA, CLASS RESPONSE, A. Oral questions., , 1. Solid: Ice, Liquid : Water, Gas : Steam, , 2. After condensation, the water droplets floating in the air along with, dust particles form clouds., , 3. A continuous movement of water from the Earth’s surface and water, bodies as water vapour to the atmosphere and from atmosphere back, to the Earth’s surface as rain is called water cycle., , B. Science quiz., , 1. Evaporation and transpiration, , 2. Soluble salts or high salt content of water, , 3. Evaporation, , 4. Water in saucer evaporates first because in saucer the water gets large, surface area for evaporation., , 5. Rooftop and roadside rainwater harvesting, , WORKSHEET, , , , A. Tick (/) the correct options., , 1. (d) 2. (c) 3. (b) 4. (a), , B. Circle the odd ones. Give reasons for your choice., , 1. Sea — It contains salty water, whereas others are sources of, fresh water., , 2. Lightning — It does not affect evaporation, whereas others are, factors affecting evaporation., , 3. Nitrogen — It is not a state of water, whereas others are states of, water., , 4. Ice — It does not form on condensation of water vapour,, whereas others are formed on condensation of, water vapour., , C. Fillin the blanks., , 1. solid, , 2. water, , 3. transpiration, , 4. drought, , D. State whether the following statements are true (T) or false (F)., , 1. 7 2. F 3. T, , SECTION B, A. Multiple Choice Questions (MCQs) Scientific/Practical skills., , 1. (b) 2. (c) 3. (c), , B. Very Short Answer Questions. 47 / 68, , 1. (a) water (b) ice, , (c) steam, , 2. Jaundice/dysentery/cholera/typhoid, , 3. Evaporation, Water acts as a medium for the transportation of minerals and other, nutrients from one part of plant to another., , C. Short Answer Questions., , 1. The process of releasing of extra water by plants into the air in the form, of water vapour through stomata is called transpiration., , 2. Absence of rain in a particular region for a long time leading to severe, shortage of water is called drought., , 3. (a) The problem of water shortage is increasing day by day due to the, , increasing population., (b) Puja cares for her neighbourhood. She is helpful., , 4. The reservoir of water collected over the hard, non-porous rocks below, the surface of the Earth is called groundwater or underground water., , D. Long Answer Questions., , 1. Rain is useful to us because—, , (i) It brings relief by cooling the environment especially after hot, summer days., , (ii) It is important for irrigating the crops in fields., , (iii) It maintains the supply of water on land by filling streams, lakes,, ponds and raising the water table., , 2. The life of animals living in soil gets affected by heavy rains as the land, gets covered with water. The animals like (snake and earthworm) that, live in soil come out in search of air and food., , 3. The main purpose of rainwater harvesting is not only t 48 / 68, on the surface of the Earth but also to make rainwater p. ., the ground more efficiently so as to recharge groundwater. This ground, water can then be taken out through tube wells, hand-pumps, etc., as, and when required. The advantage of rainwater harvesting is that it, increases the availability of groundwater and helps in overcoming water, shortage., , The other advantages of rainwater harvesting are—, (i) Soil erosion can be checked by rainwater harvesting., (ii) It helps to control floods., , , , (iii), During dry months one can also avail water supply for irrigation, and other purposes., , (iv) It reduces the loss of rainwater., , 4. (a) The trees absorb water from the soil through their roots., , They release excess water as water vapour by the process of, transpiration. This water vapour goes into the air and forms clouds., The roots of trees also help in deep percolation of rainwater and, enriches the water table., , (b) The flood water submerges the standing crops, ee, forests. Due to this, the plants do not get sufficie 49 / 68 se, and nutrients and they die., , (c) The problems faced by people after floods are, (i) Flood in city areas leads to water-logged roads and streets., This disrupts the traffic on road and causes inconvenience to, the people., , (ii) Floods cause extensive damage to crops. This may cause, acute food shortage and deaths due to hunger., , (iii) Floods cause serious injuries or death of domestic animals, by drowning., , (iv) When flood water recedes, it causes the spread of diseases, like malaria, dengue, cholera, dysentery and diarrhoea., , (v) Floods wash away the top layer of the soil, thus, reduces the, fertility of soil., , (vi) Floods also affect the animals living in the soil. Animals like, earthworms and snakes are exposed., , 5. (a) With increasing population, the demand of water has also, increased. Apart from drinking and using water for different, household works water is also used in agriculture for producing, food and industries for manufacturing a large variety of products., Since the freshwater is available in limited amount, thus we should, conserve water., , (b) The ways to conserve water are, (i) Plant more and more trees., , (ii) Use a bucket and a mug instead of shower while taking bath., , (iii) Close the taps tightly after using them., (iv) Avoid cleaning utensils under running water., (v) Check overflowing of water tanks. 49 / 68, (vi) Recycle waste water., (vii) Adopt rainwater harvesting to store the rainwater., (viii) Repair leaking pipelines and water taps immediately., , Se., , , , (c) The two main types of rainwater harvesting are, (i) Rooftop rainwater harvesting, (ii) Roadside rainwater harvesting, E. HOTS (Higher Order Thinking Skills) Questions., , 1. Floods and drought damage the crops and create acute food shortage, leading to increased prices of food grains, fruits and vegetables., , , , > [al Cae in tha cald winter marning radiirac wv Ties, dita ta which