gamete

A gamete is a reproductive cell carrying half of an organism's genetic instructions, ready to combine with another to make a new individual. Eggs and sperm are gametes; you can think of each as carrying one half of a recipe that only works once both halves are joined.

Gametes are produced by meiosis and are haploid, meaning they carry a single copy of each chromosome rather than the usual pair. When a sperm and egg fuse at fertilization, their two haploid sets combine into a diploid cell that has the full chromosome number again, with one copy of each gene from each parent.

Because meiosis shuffles alleles through crossing over and independent assortment, every gamete an individual makes carries a slightly different combination of gene versions. This variety among gametes, multiplied by the random pairing at fertilization, is the basis for the genetic uniqueness of each offspring.