AP BIOLOGY

Detailed explanation-1: -A cell having 23 pairs of the chromosome is called diploid. Diploid cells undergo division and their number reduces to half, i.e. produce haploid cells having only 23 chromosomes, without any pairs. These cells are also called gametes. Thus, gametes have only one sex chromosome.

Detailed explanation-2: -Humans are diploid, and most of the body’s cells contain 23 chromosomes pairs. Human gametes (egg and sperm cells), however, contain a single set of chromosomes and are said to be haploid.

Detailed explanation-3: -Every cell in the human body contains 23 pairs of such chromosomes; our diploid number is therefore 46, our ‘haploid’ number 23.

Detailed explanation-4: -Definition. Containing one copy of each chromosome. Human gametes (egg and sperm cells) are haploid, containing 22 autosomes and one sex chromosome.

Detailed explanation-5: -Homologous chromosomes have the same genes, though they may have different alleles. So, though homologous chromosomes are very similar, they are not identical. The homologous chromosomes are separated when gametes are formed. Therefore, gametes have only 23 chromosomes, not 23 pairs.