Which one of the following phenomena supports Darwin's concept of natural selection in organic evolution -
1. production of 'Dolly', the sheep by cloning
2. Development of organs from 'stem' cells for organ transplantation
3. Development of transgenic animals
4. Prevalence of pesticide resistant insects
Forelimbs of cat, lizard used in walking; forelimbs of whale used in swimming and forelimbs of bats used in flying are an example of:
1. Analogous organs
2. Adaptive radiation
3. Homologous organs
4. Convergent evolution
Variation in gene frequencies within populations can occur by chance rather than by natural selection.
This is referred to as:
1. Genetic drift
2. Random mating
3. Genetic load
4. Genetic flow
1. Shortening of jaws
2. Binocular vision
3. Increasing brain capacity
4. Upright posture
In the case of peppered moth (Biston betularia), the black-coloured form became dominant over the light-coloured form in England during the industrial revolution. This is an example of:
1. | natural selection, whereby the darker forms were selected |
2. | appearance of the darker coloured individuals due to very poor sunlight |
3. | protective mimicry |
4. | inheritance of darker colour character acquired due to the darker environment |
Select the correct statement from the following:
1. | Darwin variations are small and directionless |
2. | fitness is the end result of the ability to adapt and gets selected by nature |
3. | all mammals except whales and have seven cervical vertebrae |
4. | Mutations are random and directional |
The finches of the Galapagos islands provide evidence in favour of:
1. special creation
2. evolution due to mutation
3. retrogressive evolution
4. biogeographical evolution
An important evidence in favour of organic evolution is the occurrence of:
1. homologous and vestigial organs
2. analogous and vestigial organs
3. homologous organ only
4. analogous organ only
Variations caused by mutation, as proposed by Hugo de Vries, are:
1. | small and directionless | 2. | random and directional |
3. | random and directionless | 4. | small and directional |