Question

Theory of pangenesis was given by
A. Lamarck
B. Oparin
C. Darwin
D. Hugo de Vries

Answer 1

Hint: Pangenesis theory of hereditary claims that characteristics acquired during an organism's life were heritable.

Complete answer:
Pangenesis theory was given by Charles Darwin in 1868. He explained that each part of the body produces minute particles known as gemmules that aggregate in the body to form gamete. These gemmules contributed heritable information to the gametes. Darwin's theory of pangenesis slowly lost popularity in the 1890s because biologists' interest increased towards the theory of inheritance of acquired characteristics (IAC). In IAC theory, the pangenesis theory was not fitted completely.
- Darwin presented his work “provisional hypothesis” in the book The Variation of Animals and Plants under Domestication to fill a major gap in evolutionary theory at the time.
- He had not performed any experiment on cells to demonstrate his theory, so he called it a provisional hypothesis.
- Pangenesis theory was based on his observation of turtles, finches, and other species in different environments. Hence, this theory lacked details at cellular and molecular levels.
- Darwin gave the concept of gemmules to describe some phenomena regarding heredity, variation, and development.

So, the correct answer is ‘Darwin’.

Note:
- Francis Galton has proved Darwin’s pangenesis theory wrong by conducting a series of blood transfusion experiments in which he transfused the blood between two different colored rabbits
- De Vries proposed the intracellular pangenesis theory in 1889 that is a modified theory of pangenesis. In this theory, he argued that gemmules could only transfer between the nucleus and the cytoplasm inside a single cell.