Why is it essential that gametes contain only half the number of chromosomes found in a body cell?

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Question

Why is it essential that gametes contain only half the number of chromosomes found in a body cell?

Accepted Answer

So that the zygote formed when two gametes fuse has the normal number for the species — Award 1 mark. If gametes were diploid the chromosome number would double every generation. Halving it in meiosis and restoring it at fertilisation keeps the number constant.

Answer

So that the offspring are genetically identical to the parents

Answer

So that the zygote can divide by meiosis rather than mitosis

Answer

So that the gametes are small enough to swim

Answer

So that the zygote formed when two gametes fuse has the normal number for the species

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