121. Cosmozoic theory was given by ______.
122. Which one of the following phenomena supports Darwin’s concept of natural selection in organic evolution ?
A. Development of transgenic animals
B. Production of ‘Dolly’ the sheep by clothing
C. Prevalence of pesticide resistant insects
D. Development of organs from ‘stem cells’ for organ transplantation
Answer : Option B
123. Retrogressive evolution is shown by ______.
Match the correct set.
Column I Column II
I. Fossil A. 345-405 million years ago
II. Devonian period B. Fossillium
III. Cambrian period C. 425-500 million years ago
IV. Ordovician period D. 500-600 million years ago
A. I – B, II – A, III – D, IV – C
B. I – A, II – B, III – C, IV – D
C. I – B, II – C, III – D, IV – A
D. I – B, II – D, III – C, IV – A
Answer : Option A
A. Genetic drift refers to change in allelic frequencies of a gene pool due to chance and occurs both
in large and small populations.
R. Small populations will, therefore, suffer more than larger ones.
A. If A and R both are true and R is correct explanation of A
B. If A and R both are true but R is not correct explanation of A
C. If A is true and R is wrong
D. If A is wrong and R is true
Answer : Option A
126. In a population, group of individuals of similar phenotypes are formed due to differential reproduction due to
A. genetic drift
B. natural selection
C. migration
D. selective hybridization
Answer : Option A
127. Phylogenetic evolution refers to
A. genetic relationship and evolutionary sequence
B. similar habitat
C. natural affinity of genes
D. similar character
Answer : Option C
128. Genetic drift occurs when few individuals of a colonize, the phenomenon is
A. bottleneck effect
B. assortative mating
C. founder’s effect
D. random mating
Answer : Option D
129. Sympatric speciation arises due to
A. non-overlapping population of the same area
B. geographical isolation
C. overlapping population of the same area
D. non-reproductive population of the same area
Answer : Option D
130. Hardy – Weinberg equilibrium is known to be effected by gene flow, genetic drift, mutation, genetic recombination and