Somatic cells are the non-reproductive cells of an organism, while gametes are the reproductive cells, such as sperm and egg cells. In animals, somatic cells typically have a diploid number of chromosomes, meaning they have two copies of each chromosome, one inherited from each parent. Gametes, on the other hand, have a haploid number of chromosomes, meaning they have only one copy of each chromosome.

Therefore, if a somatic cell has 30 chromosomes (diploid number), the gametes produced by that organism will have 15 chromosomes each (haploid number). The process of meiosis, which produces gametes, reduces the chromosome number by half to ensure that fertilization, the union of two gametes, results in a diploid zygote with the correct number of chromosomes.