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Assertion (A): There… (Class 12 Biology SQP 2026-27, Q14)

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BiologyCBSE Class 12 · Sample paper, session 2026-27 · 1 mark · Assertion-reason

CBSE Class 12 Biology sample paper 2026-27: question 14

From the official CBSE sample question paper for 2026-27, section A, question 14, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q14 · 1 mark · Assertion-reasonCompetency-basedPrinciples of Inheritance and Variation

Assertion (A): There is no variation in the percentage recombination due to loosely or tightly linked genes.
Reason (R): Linked genes result in occurrence of higher proportion of parental gene combinations.

  1. (A)Both A and R are true and R is the correct explanation of A.
  2. (B)Both A and R are true but R is not the correct explanation of A.
  3. (C)A is true but R is false.
  4. (D)A is False but R is true.

Source: official sample paper from cbseacademic.nic.in (PDF). See it in the full Sample paper 2026-27.

Hints

Open one hint at a time and try again before the next.

Hint 1

Recall Morgan's Drosophila crosses.

Hint 2

Does the distance between genes affect the frequency of crossing over?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Tightly linked genes show low recombination and loosely linked genes show higher recombination, so A is false.

  2. Linked genes do produce mostly parental combinations, so R is true. Option (D).

    1 mark

Answer: (D)

Where the marks are

  • Judges A false and R true (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Principles of Inheritance and Variation, one at a time, marked against the answer key and marking points.Back to the full paperSample paper 2026-27: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.