A gamete is a mature male or female germ cell usually possessing a haploid (unpaired) set of chromosomes, and capable of initiating formation of a new diploid individual, or zygote, by fusion with a gamete of the opposite sex; this process is called fertilization.
Gametes develop from precursor cells called gametocytes by the process of gametogenesis. In both sexes the gametocytes undergo meiosis which halves the number of chromosomes. However, the timing of events and the size and number of gametes produced are very different in the male and female.
The gametes of some primitive organisms are identical cells capable of swimming in water, but in most species only the male gamete (sperm) is mobile while the female gamete (egg or ovum) is a large static cell. In higher plants, the male gametes or pollen are produced by the anthers and the female gametes (ovules) by the ovary. In animals gametes are produced by the gonads, namely the testes in the male and the ovaries in the female.