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The growth of pollen tubes towards ovule...

The growth of pollen tubes towards ovules is due to

A

hydrotropism

B

chemotropism

C

geotropism

D

phototropism

Text Solution

Verified by Experts

The correct Answer is:
B
The growth of a pollen tube towards ovule is induced by a chemical (sugar) substance secreted by the ripened stigma of flower into the style towards ovary.
It is an example of chemotropism, pollen grain responds to stimulus by growing a polen tube in downward direction, towards ovule for fertilisation.
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