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MODEL PAPER 4 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 43 Marks
Question
What are the main features of mutation theory?
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Answer

This theory was given by deVries. Some of the features of this theory are as follow:
i. Mutations cause evolution and not the minor variations (heritable) as mentioned by Darwin.
ii. Large differences arise suddenly in a population.
iii. Mutations are random and directionless.
iv. The mutation causes speciation (formation of new species), also known as saltation (single step, large mutation).
v. Mutations which are inheritable in nature are the part of the evolution process.
vi. Evolution is discontinuous, not a gradual process.

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