1. Of the following which one pollutes the air of a big city?
2. In a natural community, the primary consumers are __________
3. Ozone layer above the surface of Earth provides a shield against _______
B. Ultra -violet rays
C. Gamma rays
D. Infra -red rays
4.The permissible upper limit of Arsenic in water is _____
A. 0.005 gm/litre
B. 0.005 mg/litre
C. 0.05 mg/litre
D. 0.05 gm/litre
5.Ground water in the Bengal basin is mostly contaminated by __________
6. The ____________ of a species describes the trophic function it fills in its environment.
C. Carrying capacity
D. Biotic potential
7.Heavy metal pollution of water is caused by ________
A. Domestic sewage
B. Wood burning
C. Acid Plants
8. Which of the following is biodegradable?
B. D. D. T.
9.Bacteria and fungi act as ____________ within an ecosystem.
A. Primary producers
B. Primary consumers
C. Secondary consumers
10. The largest ecosystem of the Earth is ____
Answers: 1.C 2.A 3.B 4.C 5.D 6.A 7.A 8.A 9.D 10.B