A scinice question i dont understand?

Question

A mule is the offspring of a horse and a donkey. A donkey sperm contains 31 chromosomes and a horse egg 32 chromosomes, so the zygote developes normally. The combined set of chromosomes is not the problem in mitosis, and the mule combines some of the best charcteristics of horses and donkeys. However, a mule is sterlile; meiosis cannot occur normally in its testes or ovaries. Explain why mitiosis is normal in cells contaning both horse and donkey chromosomes but the mixed set of chromosomes interferes with meiosis.

Answer 1

A donkey has 62 chromosomes(sperm 31) and a horse has 64 (egg 32), leaving the mule with an uneven number of chromosomes at 63, rendering the mule sterile.

They have trouble making sperm or eggs because their chromosomes don’t match up well. And, to a lesser extent, because of their chromosome number.

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