In which condition the gene ratio remains constant for any species?
1. Sexual selection
2. Random mating
3. Mutation
4. Gene flow
Darwin's theory of pangenesis shows similarity with theory of inheritance of acquired characters then what will be correct according to it?
1. Useful organs become strong and developed while useless organs become extinct. These organs help in struggle for survival
2. Size of organs increase with ageing
3. Development of organs is due to will power
4. There should be some physical basis of inheritance
Presence of gills in the tadpole of frog indicates that
1. fishes were amphibian in the past
2. fishes evolved from frog-like ancestors
3. frogs will have gills in future
4. frogs evolved from gilled ancestors
Reason of diversity in living being is
1. mutation
2. gradual change
3. long term evolutionary change
4. short term evolutionary change
Which of following is closest relative of man?
1. Chimpanzee
2. Gorilla
3. Orangutan
4. Gibbon
When two species of different geneology come to resemble each other as a result of adaptation, the phenomenon is termed
1. divergent evolution
2. micro-evolution
3. co-evolution
4. convergent evolution
Theory of natural selection dwells on
1. role of environment in evolution
2. natural selection acting on favourable variations
3. changes in gene complex resulting in heritable variations
4. None of the above
Which one of the following options gives one correct example each of convergent evolution and divergent evolution?
Convergent evolution | Divergent evolution |
1. Eyes of Octopus and mammals | Bones of forelimbs of vertebrates |
2. Thorns of Bougainvillea and tendrils of Cucurbita | Wings of butterflies and birds |
3. Bones of forelimbs of vertebrates | Wings of butterfly and birds |
4. Thorns of Bougainvillea and tendrils of Cucurbita | Eyes of Octopus and mammals |
Parallelism is
1. adaptive divergence
2. adaptive divergence of widely separated species
3. adaptive convergence of widely different species
4. adaptive convergence of closely related groups
The concept of chemical evolution is based on
1. crystallization of chemicals
2. interaction of water, air, and clay under intense heat
3. effect of solar radiation on chemicals
4. the possible origin of life by the combination of chemicals under suitable environmental conditions