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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 : Test cross is a back cross.
Reason: In test cross, individual is crossed with recessive paren.
✓

Answer

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

Explanation:

Backcross is cross which is performed between hybrid and one of its parents. ln test cross, the individual is crossed with recessive parent. It is called a test cross, because it is used to test whether an individual is homozygous or heterozygous (hybrid).

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