Question

Darwin’s theory of pangenesis proposes_________.
(a) Some physical basis of inheritance.
(b) Development of useful organs and degeneration of useful organs
(c) Increase in organ size with age.
(d) Development of organs due to will power.

Answer 1

Hint:Darwin suggested the theory of pangenesis which emphasized the fact that all organs in our body produce some factor (which was unknown at that time) which is carried to the next generation through sexual reproduction.

Complete answer:
The word pangenesis is Greek and can be broken down as – pan + genesis. Pan means whole and genesis means birth. This theory proposed that each part of the body continuously produces its own type of small organic particles called gemmules which are transferred to the offspring from their parents. These gemmules are aggregated in the gonads and hence are transferred during sexual reproduction.
So, the correct answer is ‘some physical basis of inheritance.’

Additional Information: Along with inheritance, Darwin’s theory of pangenesis also emphasized the concepts of sexual reproduction and cellular regeneration. The gemmules were also referred to as pangenes by Darwin. He said that these gemmules are shed by all types of organs and they enter into the bloodstream which then collects them in gonads. Their accumulation was thought to occur under influence of some sort of ‘mutual affinity’. Each gemmule was said to be specifically related to a certain body part and did not contain information about the entire organism.

Note: The statement ‘Development of useful organs and degeneration of useful organs’ is the basis of the theory of evolution which was also stated by Darwin. ‘Increase in organ size with age’ simply relates to growth. Hence, these two options are incorrect. ‘Development of organs due to will power’ has no scientific basis as such.