set 2 MCQ Questions & Answers Detailed Explanation

Question : 1

The primitive atmosphere of earth contained water vapours, hydrogen, ammonia and

a) O₂

b) N₂

c) CO₂

d) CH₄

Question : 2

Darwin’s theory of natural selection is based on

a) Survival of the fittest

b) Over production

c) Struggle for existence and variation

d) All of the above

Question : 3

During the post-fertilisation period the ovules develop into __________ and the ovary matures into a _________.

a) A – flower; B – seed

b) A – seeds; B – fruit

c) A – fruit; B – seeds

d) A – seeds; B – flower

Question : 4

Which one is linked to evolution?

a) Competition

b) Variation

c) Extinction

d) Reproduction

Question : 5

Group of organisms that closely resemble each other and freely interbreed in nature, constitute a

a) family

b) species

c) genus

d) taxon