The male gamete or sex cell that contains the genetic information to be transmitted by the male, exhibits autokinesia, and is able to effect zygosis with an ovum. The human s. is composed of a head and a tail, the tail being divisible into a neck, a middle piece, a principal piece, and an end piece; the head, 4–6 μm in length, is a broadly oval, flattened body containing the nucleus; the tail is about 55 μm in length. SYN: sperm cell, sperm. [G. sperma, seed, + zoon, animal]
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sper·ma·to·zo·on -'zō-.än, -'zō-ən n, pl -zoa -'zō-ə a motile male gamete of an animal usu. with rounded or elongate head and a long posterior flagellum
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(sperm)
n. (pl. spermatozoa)
a mature male sex cell (see gamete). The tail of a sperm enables it to swim, which is important as a means for reaching and fertilizing the ovum (although muscular movements of the uterus may assist its journey from the vagina). See also acrosome, fertilization.
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sper·ma·to·zo·on (spur″mə-to-zoґon) pl. spermatozoґa [spermato- + Gr. zōon animal] a mature male germ cell, the specific output of the testes. It is the generative element of the semen which serves to fertilize the oocyte, and contains the genetic information to be transmitted to the zygote by the male. It consists of a head (or nucleus), a neck, a middle piece, and a tail with an end piece. Spermatozoa, formed in the seminiferous tubules, are derived from spermatogonia, which first develop into spermatocytes, which, in turn, undergo meiosis to produce spermatids; the spermatids then differentiate into spermatozoa. Called also sperm. spermatozoal adj
Human spermatozoon: side view (in cross-section) and flat view.
Medical dictionary. 2011.