21- Which of the following is a bio-degradable substance?
(A) Plants
(B) Polythene
(C) Ponds
(D) All of the above
22- Which of the following is a non-biodegradable substance?
(A) Plants
(B) Plastic
(C) Water
(D) Ponds
23- Which of the following is an example of producers?
(A) Lion
(B) Cow
(C) Green Plants
(D) Tiger
24- Which of the following is an example of herbivores?
(A) Goat
(B) Lion
(C) Tiger
(D) Cow
25- ………………..is an omnivores animal.
(A) Cow
(B) Hawk
(C) Lion
(D) Man
26- The formula of Ozone is
(A) O3
(B) O4
(C) O5
(D) O6
27- In a food chain, third trophic level is always occupied by
(A) Omnivores
(B) Carnivores
(C) Herbivores
(D) Decomposer
28- Which of the following is an example of bio-degradable pollutant?
(A) Water
(B) Plants
(C) DDT
(D) Animals
29- A Detritus food chain begins with ……………….
(A) Carnivores
(B) Composer
(C) Producer
(D) Decomposer
30- Ozone is a molecule formed by three atoms of ………..
(A) Oxygen
(B) Hydrogen
(C) Nitrogen
(D) None of the above
ANSWERS:
21-(A), 22-(B), 23-(C), 24-(D), 25-(D), 26-(A), 27-(B), 28-(C), 29-(D), 30-(A)