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Question
Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.
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Solution
Cross-pollination cannot occur in cleistogamous flowers. Cleistogamous flowers do not open at all. In these flowers, the anthers and stigma are close together; when the anthers dehisce in the flower buds, pollen grains touch the stigma, resulting in pollination. As a result, these flowers are always self-pollinated since they remain closed, and cross pollen cannot land on the stigma. Cleistogamous flowers can pollinate and set seeds without pollinators.
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