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Sperm Cell (Spermatozoon)

The sperm cell, or spermatozoon, is the male sex cell. Its nucleus contains the chromosomes, which bear the hereditary material of the male parent.

The sperm cell (spermatozoon) is smaller than the female sex cell (the ovum). The sperm cell has a tail-like flagellum, which gives it a shape like a tadpole and allows for motility (movement). Beginning at puberty, millions of microscopic spermatozoa are produced in the testes. It takes 46 days for the testes to produce a sperm cell, but millions are produced simultaneously. Sperm are stored in the semen, a milky fluid in the seminal vesicles and the vas deferens. During ejaculation, semen is released through the urethra, a tube that runs through the penis. If ejaculation takes place during sexual intercourse, sperm can travel through the female uterus and into the fallopian tubes. If an egg is present in either of the fallopian tubes, a single sperm can fertilize it and pregnancy will result. Half of the chromosomes in the resulting zygote (fertilized egg) come from the ovum and half from the sperm.

See also Ovum

For Further Study

Books

Avraham, Regina. The Reproductive System. New York: Chelsea House, 1991.

—Gail B. Slap, M.D. University of Pennsylvania School of Medicine