I-placenta yimbutho ebaluleke kakhulu ejongene nophuhliso oluchanekileyo lwentsana kwisibeleko somama. Xa i-placenta isakhiwe ngokupheleleyo, umntwana ufumana indlu yakhe yokuqala (kungekho ngaphandle kwesizathu sokuthi i- placenta ibizwa ngokuba yindawo yomntwana ), okwenza kube lula ukufumana konke okufunekayo ekukhuleni nasekuphuhliseni, kwaye kwelinye icala-ukhusela umncinci omncinci kwizinto ezinobungozi kunye nezinye izinto ezingabalulekanga, ekhona emzimbeni womama. Ukongezelela ekuboneleleni nge-fetus ngezinto ezincedo, i-placenta inoxanduva lokunikezelwa kwe-oksijini kunye nokurhoxiswa kwemveliso yerkunkuma.
Ukuqulunqwa kwe-placenta ngexesha lokukhulelwa
Kunzima ukuchonga ngokuchanekileyo ixesha apho i-placenta iqalisa ukwenza, kuba isigaba sokuqala sinokubakho kwi-7 ngosuku emva kokukhulelwa. Kule ngongoma, i-embryo iyancipha kwi-uterine mucosa, ihlala kwindawo ebizwa ngokuba yi-lacuna, ezaliswe ngegazi lomama. Ngeli xesha, i-chorion ikhula-imvulophu yangaphandle ye-fetus, leyo ingaqinisekiswa ngokuqinisekileyo ngokuba yi-precursor ye-placenta.
15-16 iveki yokukhulelwa - eli lixesha lokwakheka kwepentecenta. Ngeveki ye-20, xa ilungu lilungele ukusebenza ngokuzimeleyo, ukusekwa kwepentecenta kuphelile.
Kwixesha eliqhelekileyo lokukhulelwa ngaphandle kweengxaki kunye neentsholongwane, i-placenta yenziwa kwinqanaba langaphambili okanye ngaphambili. Isikhathi sokubunjwa kwe-placenta senziwa ngenxa yeempawu zomzimba ngamnye, kodwa njengomthetho, ngeveki yama-36 yokukhulelwa lilungu lifikelela ekuvuthweni kwalo okusebenzayo. Ngokukhawuleza ngaphambi kokuzalwa, i-placenta ine-2 ukuya kwe-4 cm, kwaye ububanzi bufikelela kwi-18 cm.
Placenta emva kokuzalwa
Kungakhathaliseki ukuba zingaphi iiveki i-placenta yenziwa, ilungu lihamba ngeesigaba ezine zokukhula ngexesha lokukhulelwa. Okumangalisa kukuba, ngaphambi kokuba kuzalwe i-placenta yimeko yokuguga ngokomzimba - ubukhulu bayo buyancipha kancane, kwaye iityuli zibeka phezu komhlaba. Le nqanaba lesine lokukhula kwepentecenta .
Emva kokuzalwa, i-placenta ihlukaniswe kwiindonga ze-uterus ngokuzimela ngaphandle kwemizuzu eyi-15-20. Kwezinye iimeko, kunokuthatha ixesha elide - ukuya kwiminyaka engama-50. Ugqirha kufuneka ahlolisise ngenyameko intembeko ye-placenta ukuze aqiniseke ukuba akukho ziqhezu ezishiywe kwisibeletho ezingabangela ukuvuvukala. Emva koko i-placenta ithunyelwa kwisifundo se-morphological, ngokweziphumo apho kunokwenzeka ukuvavanya inkambo yokukhulelwa kunye nezizathu zokungaphambuki.