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From Nordan Symposia
Jump to navigationJump to searchCreated page with 'File:lighterstill.jpgright|frame ==Origin== [http://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLI...'
[[File:lighterstill.jpg]][[File:3d_human_reproductive_cells.jpg|right|frame]]
==Origin==
[http://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English], from Middle French ''esperme'', ''sperme'', from Late Latin ''spermat''-, ''sperma'', from [[Greek]], [[literally]], [[seed]], from ''speirein'' to [[sow]]
*[http://en.wikipedia.org/wiki/14th_century 14th Century]
==Defiinitions==
*1a : semen
:b : a [[male]] gamete; especially : spermatozoon
*2: a product of the sperm whale
==Description==
'''Sperm''' refers to the [[male]] [[reproductive]] cells. In the types of [[sexual]] reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell. A uniflagellar sperm cell that is motile is referred to as a [http://en.wikipedia.org/wiki/Spermatozoon spermatozoon], whereas a non-motile sperm cell is referred to as a spermatium. Sperm cells cannot divide and have a limited life span, but after fusion with [http://en.wikipedia.org/wiki/Ovum egg cells] during fertilization, a new [[organism]] begins developing, starting as a totipotent zygote.[citation needed] Sperm develops in the [http://en.wikipedia.org/wiki/Testicles testicles].
The sperm cell consists of a head, a midpiece and a tail. The head contains the [[nucleus]] with densely coiled chromatin fibres, surrounded anteriorly by an [http://en.wikipedia.org/wiki/Acrosome acrosome], which contains enzymes used for penetrating the female egg. The midpiece has a central filamentous core with many mitochondria spiralled around it, used for [http://en.wikipedia.org/wiki/Adenosine_triphosphate ATP] production for the [[journey]] through the female [http://en.wikipedia.org/wiki/Cervix cervix], uterus and uterine tubes. The tail or "[http://en.wikipedia.org/wiki/Flagellum flagellum]" executes the lashing movements that propel the spermatocyte.
During [http://en.wikipedia.org/wiki/Fertilization fertilization], the sperm provides three essential parts to the [http://en.wikipedia.org/wiki/Oocyte oocyte]: (1) a signalling or activating factor, which causes the metabolically dormant oocyte to activate; (2) the haploid paternal [http://en.wikipedia.org/wiki/Genome genome]; and (3) the [http://en.wikipedia.org/wiki/Centrosome centrosome], which is responsible for maintaining the [http://en.wikipedia.org/wiki/Microtubule microtubule] system.[http://en.wikipedia.org/wiki/Sperm]
[[Category: Biology]]
==Origin==
[http://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English], from Middle French ''esperme'', ''sperme'', from Late Latin ''spermat''-, ''sperma'', from [[Greek]], [[literally]], [[seed]], from ''speirein'' to [[sow]]
*[http://en.wikipedia.org/wiki/14th_century 14th Century]
==Defiinitions==
*1a : semen
:b : a [[male]] gamete; especially : spermatozoon
*2: a product of the sperm whale
==Description==
'''Sperm''' refers to the [[male]] [[reproductive]] cells. In the types of [[sexual]] reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell. A uniflagellar sperm cell that is motile is referred to as a [http://en.wikipedia.org/wiki/Spermatozoon spermatozoon], whereas a non-motile sperm cell is referred to as a spermatium. Sperm cells cannot divide and have a limited life span, but after fusion with [http://en.wikipedia.org/wiki/Ovum egg cells] during fertilization, a new [[organism]] begins developing, starting as a totipotent zygote.[citation needed] Sperm develops in the [http://en.wikipedia.org/wiki/Testicles testicles].
The sperm cell consists of a head, a midpiece and a tail. The head contains the [[nucleus]] with densely coiled chromatin fibres, surrounded anteriorly by an [http://en.wikipedia.org/wiki/Acrosome acrosome], which contains enzymes used for penetrating the female egg. The midpiece has a central filamentous core with many mitochondria spiralled around it, used for [http://en.wikipedia.org/wiki/Adenosine_triphosphate ATP] production for the [[journey]] through the female [http://en.wikipedia.org/wiki/Cervix cervix], uterus and uterine tubes. The tail or "[http://en.wikipedia.org/wiki/Flagellum flagellum]" executes the lashing movements that propel the spermatocyte.
During [http://en.wikipedia.org/wiki/Fertilization fertilization], the sperm provides three essential parts to the [http://en.wikipedia.org/wiki/Oocyte oocyte]: (1) a signalling or activating factor, which causes the metabolically dormant oocyte to activate; (2) the haploid paternal [http://en.wikipedia.org/wiki/Genome genome]; and (3) the [http://en.wikipedia.org/wiki/Centrosome centrosome], which is responsible for maintaining the [http://en.wikipedia.org/wiki/Microtubule microtubule] system.[http://en.wikipedia.org/wiki/Sperm]
[[Category: Biology]]
