sperm

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sperm

or

spermatozoon

(spûr'mətəzō`ən, –zō`ŏn), in biology, the male gamete (sex cell), corresponding to the female ovumovum
, in biology, specialized plant or animal sex cell, also called the egg, or egg cell. It is the female sex cell, or female gamete; the male gamete is the sperm. The study of the ovum is included in the science of embryology.
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 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 chromosomechromosome
, structural carrier of hereditary characteristics, found in the nucleus of every cell and so named for its readiness to absorb dyes. The term chromosome
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) of the male parent, and a slender whiplike process (flagellum), which provides the motility necessary for fertilizationfertilization,
in biology, process in the reproduction of both plants and animals, involving the union of two unlike sex cells (gametes), the sperm and the ovum, followed by the joining of their nuclei.
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 in a fluid medium. In higher plants the sperm is contained in the pollenpollen,
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.
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 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.

Sperm

 

in plants, a nonmotile male sexual cell, or gamete. In higher plants, sperms are nonmotile because they develop inside a pollen tube, which forms upon the germination of a pollen grain (microspore). Fertilization takes place after the pollen tube ruptures upon reaching the female sex organ—the archegonium in gymnosperms or the embryo sac in angiosperms. In gymnosperms a pair of sperms forms as a result of the division of the generative cell. One of the sperms participates in fertilization, and the other dies. Both sperms participate in the fertilization of angiosperms, one fertilizing the ovum, and the other the secondary nucleus of the embryo sac. The male gametes of pteridophytes, bryophytes, and some gymnosperms (including Cycadopsida and ginkgos) are called spermatozoids; they are flagellate and motile.

sperm

[spərm]
(histology)

sperm

1. another name for semen
2. a male reproductive cell; male gamete
References in periodicals archive ?
Mention of these exceptional nonspermatic animals leads Aristotle's attention back to sperma.
40) Even though the male parent's sperma bears the form which, in Aristotle's system, has preeminence over matter, that preeminence is minimized by virtue of the potential status of both the female and male sperma and the actual status of the female and male parents.
2 Aristotle returns to the topic of sperma and of semen in particular.
The reason is that the female is as it were a deformed male; and the menstrual blood is sperma, though in an impure condition; i.
14) In the translation of GA by Peck in the Loeb edition, sperma is routinely translated as "semen.
She states, "Unlike the medical school of Hippocrates, Aristotle taught that sperma, in its narrow sense as the seed from which an embryo grows, is secreted only by males" (p.
25) At 728a25, near the close of these considerations, he states, "Hence, plainly it is reasonable to hold that generation takes place from this process: for, as we see, the menstrual fluid is sperma, not indeed sperma in a pure condition, but needing still to be acted upon.
Horowitz, in "Aristotle and Woman," notices that Aristotle calls both semen and menstrual blood sperma, but she does not notice or find it significant that he also calls them both the principles of generation.