Question

A mule is a hybrid of parents from two different species, horses and donkeys. These species have different numbers of chromosomes: horses have 32 pairs, donkeys have 31 pairs. How many chromosomes does a mule have?

Answer 1

A mule has 63 chromosomes, as it inherits 32 from the horse parent and 31 from the donkey parent. They are sterile hybrids, and chromosome differences contribute to this sterility.

Step-by-step explanation:

A mule is the offspring of a horse (with 32 pairs of chromosomes) and a donkey (with 31 pairs of chromosomes). Therefore, the main answer to how many chromosomes a mule has is that it will have a total of 63 chromosomes. This is because the mule inherits one half of its chromosomes from each parent: 32 from the horse and 31 from the donkey, which do not form homologous pairs. The explanation for the chromosome number is that while most cells in animals are diploid, containing two sets of chromosomes (one from each parent), gametes are haploid, carrying only a single set of chromosomes. In producing a mule, one gamete from the horse and one from the donkey combine, each contributing their respective set of chromosomes to generate a unique hybrid with 63 chromosomes.

Because of the difference in chromosome number between the horse and the donkey, mules typically cannot produce offspring of their own, which is an illustration of hybrid sterility. There are potential ways to overcome hybrid sterility, such as polyploidy, where the chromosome number is increased, creating a new species.