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

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation1 Mark
MCQ
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.
Assertion : Linked gene show dihybrid ratio of $9 : 3 : 3 : 1.$
Reason: Linked gene undergo independent assortment.
  • A
    Both assertion and reason are true and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true but reason is not the correct explanation of assertion.
  • C
    Assertion is true but reason is false.
  • ✓
    Both assertion and reason are false.
✓

Answer

Correct option: D.
Both assertion and reason are false.
Linked genes are those genes which occurs on the same chromosome while unlinked genes are the ones found on different chromosomes. Linked gene show dihybrid ratio of $3 : 1.$ Linked genes do not show independent assortment.

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