Question
How do organisms, whether reproduced asexually or sexually maintain a constant chromosome number through several generations? Explain with the help of suitable example.
✓
Answer
In both sexual and asexual reproduction, there is great importance of maintaining a constant number of chromosomes. But the process mechanism is dissimilar in both the type of reproductions.
- In case of asexual reproduction, the entire set of chromosomes is replicated and transferred to the next generation. DNA copying is accompanied by the creation of an additional cellular material, after which the DNA copies separate, each with its own cellular apparatus. Effectively, a cell divides to give rise to two cells. Thus, chromosome number remains unchanged.
- In case of sexual reproduction, the chromosome number is halved to form gametes. Then these gametes combine to restore the original chromosome number.
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