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

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYSexual Reproduction in Flowering Plants1 Mark
Question
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.
  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: Ubisch bodies are produced by glandular tape tum.
Reason: Ubisch bodies participated in the thickening of exine.
✓

Answer

  1. Both assertion and reason are true, but reason is not the correct explanation of assertion.

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Explanation:

The Ubisch bodies are produced only by the glandular tape tum. Ubisch bodies get covered with sporopollenin and thus increase thickening of exine. The Ubisch bodies are involved in the external thickening of the exine, whose pattem is laid down by the spore cytoplasm in the tetrad stage.

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