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

Maharashtra 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: Allogamy includes both geitonogamy and xenogamy.
Reason: Allogamy needs abiotic or biotic external agencies for pollination.
  • A
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • ✓
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • C
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: B.
Both assertion and reason are true, but reason is not the correct explanation of assertion.
Cross pollination is the transfer of pollen grains from the anther of one flower to the stigma of another flower, $i.e.,$ allogamy. Cross pollination is further classified depending on whether the pollination has occurred between two flowers on the same plant $($geitonogamy$)$ or between two flowers on different plants $($xenogamy$).$ Cross pollination $($allogamy$)$ is performed with the help of an external agency. The latter may be abiotic $(e.g.,$ wind, water$)$ or biotic $(e.g.,$ insects, birds, bats, snails$).$

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