Question

What would happen if gametes are formed by mitotic divisions?

Answer 1

Meiosis, in which the number of chromosomes is cut in half, is often how gametes are created (the gametes become haploid). Two gametes unite during fertilisation, restoring the original number of chromosomes.

Each gamete would have the same number of chromosomes as the parent cell, not half, if they were created by mitotic divisions rather than meiosis. The offspring would have twice as many chromosomes as usual if two of these gametes merged during fertilisation. The number of chromosomes would keep doubling with each generation. This would cause abnormalities and disturb the species' genetic stability. Meiosis is therefore necessary to maintain the same number of chromosomes from generation to generation.