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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: Megaspore mother cell undergoes meiotic division.
Reason: All four megaspores form female gametophyte.
  • 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.
One hypodermal nucellar cell of the micropylar region differentiates into sporogenous cell. It forms a diploid megaspore mother cell or megasporocyte. The megaspore mother cells undergo meiosis and forms a row of four haploid megaspores. Only the chalazal megaspore remains functional, while the other three degenerates. The functional megaspore enlarges and gives rise to female gametophyte, also called embryo sac.

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