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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 : A gene may have several allelomorphs.
Reason: Wild form can mutate in more than one ways.
✓

Answer

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

Explanation:

According to Mendel's concept ofinheritance, each gene had two alternative forms or allelomorphs, one being dominant and the other recessive. Practically, the wild form can mutate in several ways. The mutant form can also mutate once again to give rise to another mutant form. Therefore, a gene can have more than two allelomorphs. These allelomorphs make a series of multiple alleles.

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