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Question
Describe any two devices in a flowering plant which prevent both autogamy and geitonogamy.
Solution
Two devices which prevent both autogamy and geitonogamy in flowering plants are:
1) In some species, pollen release and stigma receptivity are not synchronised. In this case, either the pollen is released before the stigma becomes receptive or the stigma becomes receptive much before the release of the pollen.
2) In another method, the anther and stigma are placed at the different position so that the pollen does not come in contact with the stigma of the same flower.
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