Q. Select the correct statement from the following :
- Mutations are random and directionless.
- Darwinian variations are small and directionless.
- Fitness is the end result of the ability to adapt and get selected by nature.
- All mammals expect whales and camels have seen servical vertebrae.
Solution :
Correct option : C (i)Mutations are random changes taking place at the level nucleotide sequence in DNA. Mutation is directionless means that nobody knows if it might result in something beneficial for the organism or harmful. (ii)Darwinian variations are small and directional. (iii) Fitness means reproductive fitness in the context of evolution. Population of all organisms have variations in characteristics, which make them adapt better to the environment. Some of these characteristics enable individuals to survive better in natural conditions and reproduce. This is called survival of the fittest. (iv)The organisms which adapt well in the environment will be selected by nature and will survive more in nature. This is called natural selection. Adaptability is inherited and fitness is the end result of the ability to adapt and get selected by nature. (v)So, the correct options are ‘Mutations are random and directionless.’ and ‘Fitness is the end result of the ability to adapt and get selected by nature.’