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sperm |
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sperm or spermatozoon (spûr'mətəzō`ən, –zō`ŏn), in biology, the male gamete (sex cell), corresponding to the female ovum ovum (ō`vəm), in biology, specialized plant or animal sex cell, also called the egg, or egg cell. ..... Click the link for more information. in organisms that reproduce sexually. In higher animals the sperm is produced in the testis of the male; it is much smaller than the ovum and consists primarily of a head, whose nucleus bears the hereditary material (see chromosome chromosome (krō`məsōm') ..... Click the link for more information. ) of the male parent, and a slender whiplike process (flagellum), which provides the motility necessary for fertilization Cross-fertilization indicates fusion of a sperm of one hermaphroditic plant or animal with an ovum of another, as distinguished from self-fertilization, in which ovum and sperm of the same individual are fused. ..... Click the link for more information. in a fluid medium. In higher plants the sperm is contained in the pollen pollen, minute grains, usually yellow in color but occasionally white, brown, red, or purple, borne in the anther sac at the tip of the slender filament of the stamen of a flowering plant or in the male cone of a conifer. ..... Click the link for more information. grain and is conveyed to the ovum by the pollen tube; in some lower plants (e.g., mosses and ferns) the sperm is actively motile. spermor spermatozoonMale reproductive cell. In mammals, sperm are produced in the testes and travel through the reproductive system. At fertilization, one sperm of the roughly 300 million in an average ejaculation (see semen) fertilizes an egg (see ovary) to produce an offspring. At puberty, immature cells (spermatogonia) begin a maturation process (spermatogenesis). A mature human sperm has a flat, almond-shaped head, with a cap (acrosome) containing chemicals that help it penetrate an ovum. It is essentially a cell nucleus, with 23 chromosomes (including either the X or Y that determines the child's sex). A flagellum propels the sperm, which may live in a woman's reproductive tract for two to three days after sexual intercourse, to the egg. Sperm may be frozen and stored for artificial insemination. sperm 1. another name for semen 2. a male reproductive cell; male gamete How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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Male factors include inadequate volume of ejaculate, sperm concentration, sperm motility, testosterone, and the toxic effect of tobacco, marijuana, heroin, cocaine, and alcohol. To date, only one study has addressed DBPs and male reproductive health wherein exposure to DBPs was associated with decrements in sperm motility (Fenster et al. Each type of ASAB may interfere directly or indirectly with a different step in the fertilization process, including sperm motility, sperm penetration of the cervical mucus, sperm capacitation and the acrosome reaction, sperm binding and penetration of the zona pellucida, zona reaction, gamete fusion, cleavage, and embryo development. |
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