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Class 7
Science
Reproduction in Plants
explain the difference between self pollination an...

Question:
Explain the difference between self-pollination and cross-pollination.

Answer:

Pollination is the transfer of pollen grains from the anther to the stigma of the flower which can be achieved by biotic (insects, birds etc.) and abiotic (wind, water etc.) pollinating agents. On the basis of pollinating mechanism, plants can be grouped into two mating systems: self- pollinated and cross- pollinated.

Self- Pollination	Cross Pollination
1. The pollen grain moves to the female part of the same flower or different flower of the same plant species.	1. The pollen grains are transferred to the flower present on the different plant.
2. Transfer to the same flower is autogamy; and to another flower on the same plant is geitonogamy.	2. Cross- pollination is also known as allogamy.
3. No genetic variation occurs.	3. High genetic variation are found.
4. Identical species are created, i.e. no new species are formed.	4. New species are formed.
5. Transfer of pollen grains are limited.	5. Transfer of pollen grains unlimited, i.e. in large amount.

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Question:
Explain the difference between self-pollination and cross-pollination.

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Question:
Explain the difference between self-pollination and cross-pollination.