What term refers to the number of chromosomes found in sex cells?

The term that refers to the number of chromosomes found in sex cells is haploid. In biological terms, haploid cells contain half the number of chromosomes typically found in the somatic (body) cells of an organism. This is crucial in the process of sexual reproduction, as haploid sex cells (gametes) combine during fertilization to form a diploid organism, restoring the full set of chromosomes.

In contrast, diploid refers to cells that have two sets of chromosomes, which is the case for most somatic cells in an organism. Polyploid describes cells that have more than two complete sets of chromosomes, a condition found in certain plants and some animal species, but not typical of human sex cells. Trisomy is a specific genetic condition resulting from an extra chromosome; it deals with chromosomal abnormalities rather than the standard number of chromosomes in sex cells. Thus, haploid specifically and accurately describes the chromosome count in sex cells.