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Question
How do organisms, whether reproduced asexually or sexually maintain a constant chromosome number through several generations? Explain with the help of suitable example.
Solution
The maintainance of chromosomal number of utmost importance when an organism is reproducing either sexually or asexually. The mechanism is different in both the type of reproductions.
In case of asexual reproduction the whole set of chromosomes is replicated and transferred to the next generation. For example, reproduction of Amoeba by binary fission.
In case of sexual reproduction the chromosome number is halved to form gametes. Then these gametes fuse together to restore the original chromosome number.
For example, in case of human beings, there are 46 chromosomes present in a normal cell but during reproduction gametes are generated which contain half the number of chromosomes i.e 23. Now, when female gamete containing 23 chromosomes is fused with male gamete with 23 chromosomes, the number is restored to original 46 (23+23).
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