zygote

/ˌzaɪˈgoʊt/

/ˈzaɪgəʊt/

Other forms: zygotes

A zygote is a fertilized egg.

The sperm cell (spermatozoon) and the egg (ovum) each have only half the genes of the parent cell — they're haploid cells. When the spermatozoon fertilizes the ovum, the resulting cell has the full complement of genes, so it's a diploid cell. The diploid cell then divides rapidly, becoming first an embryo, then a fetus. The word zygote comes from the Greek word for yoke — joining two things together, like hitching two oxen together to pull a plow.

Definitions of zygote

1. noun

   (genetics) the diploid cell resulting from the union of a haploid spermatozoon and ovum (including the organism that develops from that cell)
   synonyms: fertilized ovum

   types:

   heterozygote

   (genetics) an organism that has two different forms of a particular gene, resulting in different outcomes in the offspring

   homozygote

   (genetics) an organism having two identical alleles of a particular gene and so breeding true for the particular characteristic

   type of:

   cell

   (biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals