Page 2 - 3- Home Assignment I (Obj & Subj)-Water; water pollution

(d) photosynthesis
9 What is the purpose of rain-water harvesting?
(a) To hold rain water on the surface of the earth.
(b) To recharge ground water.
(c) To use water for the irrigation of crops.
(d) To rear fish
10 The pH range most conducive for life of fresh water plants and animals is
(a) 6.5 – 7.5
(b) 2.0 – 3.5
(c) 3.5 – 7.0
(d) 9.0 – 10.5

Subjective

1. Name two freshwater resources, which provide freshwater for human 1 E
use.
2. Name two measures that can be taken to reduce water pollution. 1 E
3. What is the importance of water for plant life? 1 Av
4. Water is essential for life? Why? State three points. 3 Av
5. (i) Though large oceans surround the land masses, the water needs to 3 D
be conserved. Explain.
(ii) How is the life of organisms living in water affected when water gets
polluted?
6. (a) There is mass mortality of fishes in a pond. What may be the 3 D
reasons?
(b) Name the properties of potable drinking water.