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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: Hybrids are generally back crossed.
Reason: Back cross is done to increase the traits of the parent.
✓

Answer

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

Explanation:

Back cross is a cross which is performed between hybrid and one of its parents. In plant breeding, back cross is performed a few times in order to increase the traits of that parent. for example, a crop plant is crossed with a wild variety in order to obtain its disease resistance. In the process, most good traits of the crop plant get diluted. The hybrid is, therefore, repeatedly crossed with parent crop plant in order to transfer the good traits back into it.

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