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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: Colpa a urea is a specialised pollinating agent of orchid Ophrys speculum.
Reason: Male Colpa mistakes the Ophrys flowers for female partner.
✓

Answer

  1. Both assertion and reason are true, and reason is the correct explanation of assertion.

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

For its pollination the orchid Ophrys speculum has picked on the most selective attraction in the entire animal kingdom. It is pollinated by a hairy wasp, Colpa a urea. The wasp has a fixed habit whereby its males leave the burrows for above - ground existence about four weeks before the females emerge for the open air mating. The orchid opens its flowers about the same time the males appear, and they possess an appearance and odour similar to those possessed by the female wasp. The inexperienced males mistake the Ophrys flowers for their female counterparts and land to perform the act of pseudo-copulation. The insect repeats the act with a number of orchid flowers and carries pollinia from one flower to another.

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