13.
Theory of natural selection was propounded by
Answer : B. Charles Darwin
14.
Generally biological activity is relatively little
Answer : A. below 0 C or above 50 C
15.
In 1.2 years half 64mg of radioactive isotope decays. The amount present after 6 years is
Answer : D. 2 mg
16.
The first bird is believed to have appeared on the surface of the earth
Answer : C. 150 million years ago
17.
Which one of the following animals stores water in the intestine?
Answer : B. Camel
18.
Terrestrial produces
Answer : D. Uric acid