Page 179 - Science Class 07

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A. Tick (3) the correct op on.
1. Which of the following is not a cause of rapid growth in waste accumula on?
(a) Urbanisa on (b) Industrialisa on
(c) Consumerism (d) Deforesta on
2. Which of the following is a non-biodegradabel waste?
(a) Clothes (b) Paper
(c) Food materials (d) Synthe c polymers

3. Which of the following is a harmful gaseous waste?
(a) Carbon monoxide (b) Lead oxide
(c) Sulphur dioxide (d) All of these
4. Which of the following waste materials takes minimum me to be decomposed?

(a) Plas c (b) Leather
(c) Glass (d) Co on
5. Which of the following disease is not caused by contaminated water?

(a) Jaundice (b) Cholera
(c) Diarrhoea (d) Asthma
B. Fill in the blanks.
1. We should develop _____________ effec ve and _____________ technique for the
disposal of wastes properly.
2. _____________ wastes do not remain accumulated in the environment for a long me.

3. _____________ wastes are not decomposed by micro-organisms and remain accumulated
in the environment for a longer period of me.

4. In big ci es, there is a huge network of _____________ system to transport sewage to its
des na on.
5. In _____________ treatment, water is passed through clear quartz tubes exposed to
intense ultraviolet rays.
C. Give examples of five waste materials from biodegradable and non-biodegradable wastes.
1. Biodegradable : _______________________________________________________

_________________________________________________________________________
2. Non-Biodegradable : _______________________________________________________
_________________________________________________________________________
D. Write True or False.

1. Due to industralisa on, wastes are accumula ng in the environment.
2. Improper waste management can cause several environmental problems.
3. It is the duty of government as well as people to take ini a ve for the
proper disposal of wastes.

Science-7 179