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Davrai duyumi taqsimshavii meyozi

In davra umuman ba taqsimshavii mitozi monand buda, tanho farqiyat dar on ast, ki in hujayraho gaploidiand (1p 2s). Dar anafazai II sentromeraho (kashishkhurakho), ki khromatidhoi khohariro payvasta nigoh medorand, dar yak khromosoma taqsim meshavand. Az hamin vaqt khromatidho chun dar mitoz khromosomahoi mustaqili dukhtariro tashkil karda, ba qutbhoi bo ham muqobil ravona megardand. Bo khotimai telofazai duyum, ravandi meyozi ham ba okhir rasida, az yak hujayrai ibtidoi (avvala)-i jinsi 4 hujayrai gaploidi bo dastai khromosomai 1p 1s paydo meshavad.

Hamin tavr, mohiyati davrai rasish az on iborat ast, ki dar du davri taqsimshavii meyozi miqdori khromosomahoi hujayrahoi jinsi du barobar va miqdori KDN boshad, 4 barobar kam meshavad.

Mazmuni biologii taqsimshavii duyumini meyozi dar on ast, ki miqdori KDN bo miqdori khromosomaho barobar megardad (1:1). Dar fardhoi jinsi narina onho dar 4 hujayrai gaploidi, ki dar natijai meyozi paydo shudaand, joygirand va dar oyanda ba gametaho tabdil meyoband. Dar fardhoi jinsi modina dar natijai nobarobarii meyozi faqat yake az in hujayraho qobiliyati inkishof doshta, hujayratukhmro hosil mekunad. Se hujayrai digari dukhtari khele khurd buda, ba hissachahoi reduksioni tabdil meyoband va sipas mahv meshavand.

Mohiyati biologii paydo shudani yak hujayratukhmi tanho va nobud gashtani se oositi norasida, ki onhoro az nigohi genetiki hissachai reduksioni menomand, dar hujayra imkoniyati zakhira shudani moddahoi gizoii baroi inkishofi janin lozimro nigoh medorad. Vobasta ba miqdori zardi dar hujayratukhm gametahoi modina ba navho taqsim meshavand.

Dar neshtarshaklon zardi kam buda, on dar sitoplazma barobar pahn gardidaast. Vale dar khazandagon va parrandagon zardi bisyor buda, dar yak tarafi hujayra jam gashtaast. In qismro nashvi (gizodihanda) menomand. Qismi digar, ki dar on zardi kam ast va hujayra yadro dorad, qismi animali (az lotini animalis – hayvon) menomand.

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