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Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction in Flowering Plants1 Mark
MCQ
For 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: Pollen wall is made up of two walls, the intine and the exine.
Reason: Both the walls have depositions of sporopollenin.
  • 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.
  • ✓
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: C.
Assertion is true, but reason is false.
The pollen wall comprises two principal layers, the inner one is called intine and the outer exine. The intine is pecto$-$cellulosic in nature, as is the primary wall of the somatic cells. The exine is composed chiefly of a class of material called sporopollenin.

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