Gametogenesis - it ... zigaba gematogeneza neentlobo ukuzala

Namhlanje sinikele ukuba wenze ngaphandle inkqubo gametogenesis. Ngokufutshane kwaye kwacaca kakhulu, oko kukuthi inkqubo yophuhliso cell lwegciwane. Njengokuba sele kucaca, eli nqaku liza makasingelwe yokuzala. Qaphela ukuba cell ukuba iintlobo ezininzi ukuzala ngokwesondo. Sekunjalo, bonke bephela zisekelwe phezu inxaxheba gametes amabini (zesini namabhinqa). Sinikezela ukuba bayikhangele loo mbuzo ngokweenkcukacha.

syngenesis

Sele ekhankanywe ukuba ukuzala ikhutshwa phandle ngokuthatha inxaxheba kwabantu ababini ngokwesini. Baye iiseli ezikhethekileyo zokuzala, ezaziwa ngokuba gametes ziveliswa amalungu athile. Kwaye yintoni gametogenesis? Le nkqubo wokusungula iiseli yintsholongwane kakhulu, ezo eziyimfuneko ukuze zizale. Kufuneka uyazi into yokuba inkqubo ngokudibana gametes kuthiwa isichumiso. Meiosis lwegciwane line - linqanam ephambili yophuhliso cell lwegciwane. Sinikele ingqalelo kuyo kamva kancinane.

Ngoku khetha uhlobo ukuzala:

• isogamy;
• heterogamy;
• ovogamiya.

Kubalulekile ukuqaphela ukuba zahluke kwezinye iinkalo ngesakhiwo kweeseli lwegciwane. Ngokomzekelo, xa isogamy zombini inkunzi kunye gametes nemazi ziphatheka, ukongeza, ukuba babe nemilinganiselo efanayo. Le fomu ilandelayo ifana kakhulu kulowo elidlulileyo. Umahluko omkhulu phakathi yesibini - iiseli yintsholongwane ababhinqileyo makhulu amadoda, njengoko akukho nje mobile. Uhlobo lwesithathu ukuzala ethandwa, njengokuba kwenzeka kwizilwanyana ezininzi kunye nezityalo. Kulo ngobuwena, iiseli yintsholongwane imazi esisigxina yaye inkulu kakhulu into eyindoda. Kule fomu yokuzala kuthiwa gamete eyindoda - spermatozoa, okanye amadlozi, nemazi - eqandeni.

Iifom ezimbini zokuqala aqhelekile eziphilayo bakudala ezifana nezinto ezimdaka. Njani na nokuzala eukaryotes? Ngokudibana gametes inkunzi nemazi (amaqanda kunye amadlozi). Ngenxa yoko, ukufaka isichumiso, elilodwa kunye ndakubumba. Kubalulekile ukuqonda into yokuba iiseli intsholongwane ziqulathe inani chromosome obubuphinda kabini ngaphantsi kwe esiseleni somatic. Oku kuchazwa nje: Ukuba inani zofuzo yaba iiseli somatic kunye intsholongwane ye enye, kuzo zonke sizukulwana, ukuya kabini lwe zofuzo. Kutheni oku akwenzeki? Ngenxa meiosis, okt division cell.

Izinto eziluncedo ze ukuzala

umgca lwegciwane - uphuhliso iiseli lwegciwane. ukuzala ngaphandle ukuyilwa gametes akunakwenzeka. Kubalulekile ukuqaphela into yokuba ibakala gametogenesis kumadoda nabafazi iimpawu ezifanayo. Xa iinkcukacha ngakumbi, siza kuyihl 'amahlongwane le kancinane emva koko. Ngoku nawe kancinci ukuxoxa kakuhle ngokobugcisa kufuywe iingenelo uhlobo ngokwesondo. Le zizale wemvelo wabeka zemfuza. Kulo mzekelo, xa maqanda umzimba yokuzala sokuncedisa phinda ngokupheleleyo umzali wayo.

ukuzala ineendlela ezininzi:

• indibanisela yemfuza koomama zooyise, oko kukuthi, akukho okuba ikopi ingundoqo yemfuza lomzali;
• hexa, ukukwazi labantu ukuba ziziqhelanise nemiqathango emitsha ukuze ukhuseleke lweentlobo;
• lula inkqubo speciation, njalo-njalo.

spermatogenesis

Besesitshilo ngaphambili umgca intsholongwane - inkqubo yophuhliso cell lwegciwane. Ngoku thatha ujongo spermatogenesis kufutshane, oko kukuthi, ukuyilwa madlozi. Total yahlulwe izigaba ezine:

• nokuzala;
• ukukhula;
• nokwanda;
• ukwakheka.

Eqongeni ukuzala, mitotic spermatogonia hlukanisa. Emva koko, lihlaleni amadlozi elizayo kungena nqanaba lokukhula, ngoku ke igama -spermatotsity. Inqanaba lokukhula iphawulwa ukwanda kakhulu iiseli intsholongwane, lona wenza ukuba sikwazi ukwandisa umthamo kukho icytoplasm. Isigaba nokuvuthwa - amaqela amabini. Spermatocyte, nto leyo iye yaluphumelela nqanaba lokugqibela ufakwa ukwehlukana, ngaloo ndlela kusenziwa spermatocytes ezimbini. Emva koko, ngamnye kubo yahlulwe kwakhona. Lilonke, omnye spermatocytes yomyalelo yokuqala, sinokuyifumana spermatids ezine. Zakutshanje angene Isigaba sesine - ukuyilwa. Kuphela emva kwezi amanqanaba weseli isidoda kuthatha nefom kuthi.

ovogenesis

Ovogenesis - uphuhliso iiseli lwegciwane obhinqileyo (oocytes). Ngezantsi zidweliswe nechazwe nqanaba lenkqubo.

• Veliswa. Oogonia kuwabela mitosis, okubangela inani leeseli lwegciwane kwanda elizayo. Kubalulekile ukuqaphela ukuba ibakala ukuzala iwela kwinyanga yesibini amantombazana Palsy.
• Growth. Eli nyathelo ngokupheleleyo okwenza inkqubo lokukhula kweeseli lwegciwane eyindoda. Umahluko kuphela - ubungakanani iqanda lidlula ubungakanani spermatocytes elizayo, kungenxa beqokelela izondlo yokuqala.
• Yinkalo yokugqibela oogenesis - ekukhuleni. Lubonakala ngokwemizi ezimbini ezilandelelanayo yi meiosis. Xa omnye spermatocytes spermatogenesis wambumba isidoda ezine. Kwimeko enye oogenesis kweqanda iqanda unako wokusungula maqumrhu mathathu ezibandayo.

Kutheni inqubo kunabanye ngenani, kodwa zingaphantsi ngobukhulu yeqanda? Isidoda a angakhuli izondlo, njengoko umjikelo wobomi bayo kakhulu elifutshane. Eyona umsebenzi iiseli oyindoda lokuzala - ukuziswa kwezinto yezofuzo kwi eqandeni. Ngaphezu koko, kufuneka babe mobile kakhulu. Inqubo ufuna iqanda ubunzima kufa, nto leyo echaza inzuzo yazo lwamanani.