Polar bear somatic cells contain 74 total chromosomes. how many chromosomes would a polar bear egg cell contain?

The correct answer would be 37.

Egg or sperm or gametes are cells produced by the process of meiosis and carry half the number of chromosome (n) present in a parental cell (2n).

Meiosis is a type of cell division which results in the formation of four daughter cells each having exactly half the number of chromosome present in  parent cell.

The sperm unite or fertilize with egg which restore the chromosome number (2n) in the zygote.

37 chromosomes

Explanation:

The polar bear is a diploid organism. That means it has two copies of each chromosome. In the case of somatic cells, each cell then has 74 chromosomes. That is to say, two copies of each one being that one comes from the mother and the other from the father. In the case of the gametes, which are the sexual cells, i.e. egg or sperm, they are haploid. This means that each gamete has only one chromosome from each set of homologous chromosomes. This is because during meiosis (the process by which these gametes are created) four daughter cells are produced and each has half the number of chromosome present in parent cell. That means, each gamete (an egg but also a sperm) will have 37 chromosomes.

And once the sperm fertilizes the egg, the chromosome number is restored in the zygote. This zygote wll develop into a new organism (for example the polar bear) and will be diploid, so it will have 74 chromosomes in its somatic cells.