Question

___________ are heritable and have evolutionary significance.

• A. Somatic variations
• B. Genetic variations
• C. Discontinuous variations
• D. Both (b) and (c)

Answer 1

The correct option is D Both (b) and (c)

We know that the offsprings of the same parent are not alike. This means that variations occur in nature. The differences between closely related organisms are described as variations. Variations are of two types, they are the somatic variations and genetic variations.

The germinal or blastogenic variations are the variations that occur in the germplasm or germ cells of organisms. These variations are passed to the next generation (heritable) because of that it has evolutionary significance. For example - body colour, eye colour, etc.

Somatic or somatogenic variations are caused by the influence of the environment upon the body of the organism. They are neither inherited from the parents nor transmitted to the offspring, but are lost with the parent's death. For example - loss of any body parts due to accidents, better developed muscles in athletes.

The discontinuous variations are sudden and large variations. These are also called mutations and are heritable. They are transmitted to the next generation and have evolutionary significance. For example - the presence of six digits in man, long tails in Japanese cocks.