Question

Before Darwin's theory of evolution, another theory existed that postulated that any physical changes that occurred in an organism through its lifetime could be transmitted to its offspring. Using one example, explain why this theory cannot be true.

Assertion (A) : In humans, if gene (B) is responsible for black eyes and gene (b) is responsible for brown eyes, then the colour of eyes of the progeny having gene combination Bb, bb or BB will be black only. Reason (R) : The black colour of the eyes is a dominant trait.

Name the term used for the traits that are exhibited externally?