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Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation1 Mark
Question
For question two statements are given-one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both assertion and reason are true and reason is the correct explanation of assertion.
  2. Both assertion and reason are true but reason is not the correct explanation of assertion.
  3. Assertion is true but reason is false.
  4. Both assertion and reason are false.
Assertion: Mutations are discontinuous variations.
Reason: Mutations occur suddenly.
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Answer

  1. Both assertion and reason are true and reason is the correct explanation of assertion.

Explanation:

Mutations are sudden unpredictable inheritable departures from the normal type without any intermediate stage. Discontinuous variations form the basis of mutation theory of evolution which was proposed by De Vries (1902).

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