. . . . . . "dozr\u00E1v\u00E1n\u00ED spermi\u00ED"@cs . "Spermatogeneze je tvorba mu\u017Esk\u00FDch pohlavn\u00EDch bun\u011Bk (spermi\u00ED). Pro spr\u00E1vn\u00FD pr\u016Fb\u011Bh spermatogeneze je zapot\u0159eb\u00ED dostate\u010Dn\u00E1 stimulace pohlavn\u00EDmi hormony (zejm\u00E9na testosteronem) a d\u00E1le ni\u017E\u0161\u00ED teplota, j\u00ED\u017E je doc\u00EDleno um\u00EDst\u011Bn\u00EDm varlat v \u0161ourku. Tvorba spermi\u00ED m\u00E1 t\u0159i f\u00E1ze: rozmno\u017Eovac\u00ED, r\u016Fstovou a zr\u00E1n\u00ED. Na po\u010D\u00E1tku v\u00FDvoje spermi\u00ED jsou spermatogonie, co\u017E jsou sam\u010D\u00ED prapohlavn\u00ED bu\u0148ky. Maj\u00ED kulovit\u00FD tvar a jsou ulo\u017Eeny na okraj\u00EDch semenn\u00FDch kan\u00E1lk\u016F. Spermatogonie se mitoticky d\u011Bl\u00ED. Jednak aby zachovaly sv\u00E9 po\u010Detn\u00ED stavy a jednak jejich d\u011Blen\u00EDm vznikaj\u00ED prim\u00E1rn\u00ED spermatocyty (spermatocyty I. \u0159\u00E1du), kter\u00E9 le\u017E\u00ED nad vrstvou spermatogoni\u00ED. Prim\u00E1rn\u00ED spermatocyty jsou diploidn\u00ED, av\u0161ak po prvn\u00EDm meiotick\u00E9m d\u011Blen\u00ED z nich vznikaj\u00ED haploidn\u00ED sekund\u00E1rn\u00ED spermatocyty (spermatocyty II. \u0159\u00E1du). Ty maj\u00ED st\u00E1le zdvojen\u00E9 chromatidy, proto z\u00E1hy doch\u00E1z\u00ED k druh\u00E9mu meiotick\u00E9mu d\u011Blen\u00ED, jeho\u017E produktem jsou spermatidy. Spermatidy jsou ji\u017E pln\u011B haploidn\u00ED a d\u00E1le se ned\u011Bl\u00ED. Spermatidy pot\u00E9 proch\u00E1z\u00ED procesem spermiogeneze, p\u0159i kter\u00E9m doch\u00E1z\u00ED ke kondenzaci j\u00E1dra, vytvo\u0159en\u00ED bi\u010D\u00EDku a ztr\u00E1t\u011B v\u011Bt\u0161iny cytoplazmy a n\u011Bkter\u00FDch organel. Nezral\u00E9 spermie putuj\u00ED p\u0159es semenotvorn\u00E9 kan\u00E1lky do nadvarlete, kde doch\u00E1z\u00ED k jejich definitivn\u00EDmu zr\u00E1n\u00ED. Cel\u00FD tento proces trv\u00E1 asi 72 dn\u00ED (\u00B1 2 dny). Spermatogeneze prob\u00EDh\u00E1 od puberty do individu\u00E1ln\u011B vysok\u00E9ho v\u011Bku a odhaduje se, \u017Ee mu\u017E za sv\u016Fj \u017Eivot vyprodukuje cca 12 bili\u00F3n\u016F spermi\u00ED."@cs . "2130"^^ . . . . . . "144877"^^ . . . . "Spermatogeneze"@cs . . . . . . . "tvorby spermatu"@cs . "15945962"^^ . . . "zr\u00E1n\u00ED spermi\u00ED"@cs . . . . "Spermatogeneze je tvorba mu\u017Esk\u00FDch pohlavn\u00EDch bun\u011Bk (spermi\u00ED). Pro spr\u00E1vn\u00FD pr\u016Fb\u011Bh spermatogeneze je zapot\u0159eb\u00ED dostate\u010Dn\u00E1 stimulace pohlavn\u00EDmi hormony (zejm\u00E9na testosteronem) a d\u00E1le ni\u017E\u0161\u00ED teplota, j\u00ED\u017E je doc\u00EDleno um\u00EDst\u011Bn\u00EDm varlat v \u0161ourku. Tvorba spermi\u00ED m\u00E1 t\u0159i f\u00E1ze: rozmno\u017Eovac\u00ED, r\u016Fstovou a zr\u00E1n\u00ED. Na po\u010D\u00E1tku v\u00FDvoje spermi\u00ED jsou spermatogonie, co\u017E jsou sam\u010D\u00ED prapohlavn\u00ED bu\u0148ky. Maj\u00ED kulovit\u00FD tvar a jsou ulo\u017Eeny na okraj\u00EDch semenn\u00FDch kan\u00E1lk\u016F. Spermatogonie se mitoticky d\u011Bl\u00ED."@cs . "Spermatogeneze"@cs . . . "spermatogeneze"@cs . "19"^^ . "spermatogenezi"@cs . .