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Question
(a) Identify A, B and C in the given diagram and write their functions.
(b) Mention the role of gamete and zygote in sexually reproducing organisms.
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Solution
(a) A - Stigma, Function - The stigma is a sticky surface where the pollen lands and later germinates
B - Pollen tube, Function- It carries the pollen to the egg cell for fertilization
C - Egg cell, Function- It fuses with the male gamete and leads to the formation of zygote.
(b) Role of gametes- The gametes play an important role in the sexually reproducing organisms as they carry the entire genetic information of the organism. These gametes upon fusion result in the formation of zygote, which develops into a new individual. Any deformation in the gametes will lead to the deformity in the newly formed offspring.
Role of zygote- Zygote is the diploid cell formed by the fusion of male and female gametes during fertilization in sexual reproduction. Zygote is the first stage in the development process of an organism and it contains all the genetic information of both the parents, essential for the growth of the new organism.
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