Nguwuphi utshintsho olwenziwa ngumntwana?
Ngaphandle, iqanda le-fetal liguqulwa kancane libe yimbungu. Isakhiwo sangaphakathi saso siba nzima nakakhulu. Ngoku lifana nedisk eququzelelwe ngokukhawuleza kwezi-3 zeeseli ezilinganayo. Kwi-embryology, ngokuqhelekileyo zibizwa ngokuba ngama-embryonic sheets. Ngokukhawuleza kunikezwa izakhiwo ze-anatomical zivelise kwiinkqubo ngamnye kunye nezitho zomntwana ongakazalwa.
Ingaphandle, okanye njengoko idlalwa ngokuba yindawo engaphandle, i-ectoderm. Ngokukhawuleza ukusuka kuyo kubunjengezinto ezinjengoku:
- isikhumba;
- i inwele;
- izipikili.
Ukongezelela, iqela elingaphandle lithatha inxaxheba ngokuthe ngqo kwi-system ye-nervous, ifowuni ebonakalayo, amazinyo.
Uluhlu oluphakathi, i-mesoderm, lunikeza isistim seethambo, izicubu ezixhumeneyo, izixhobo ze-muscular, i-excretory, zesondo kunye neenkqubo zokujikeleza.
I-Endoderm, uluhlu lwangaphakathi, luyisiseko sokwakheka kwesigxina sesisu, isibindi, iingqungquthela zangaphandle.
Ukukhulelwa kancinci iiveki ezi-4, kwinqanaba lokuqhotyoshela iqanda le-fetal ukuya eludongeni lwe-uterine, inethiwekhi yemithambo yegazi iqala ukwenza. Nguye onika i- placenta.
Ngaba kunokwenzeka ukubeka ukukhulelwa ngaloo mhla?
I-HCG kwiveki ye-4 yokukhulelwa kwezabelo zokuzalwa ifikelela kwizinga lokuxilonga. Ngako oko, ukusekwa kweyona nqobo yecandelo lomzimba, umfazi angasebenzisa uvavanyo oluqhelekileyo.
Ngokuqhelekileyo, i-hormone concentration i-25-156 mMe / ml.
I-ultrasound kwiveki yesi-4 yokukhulelwa iqhutyelwa ukuqinisekisa ubungqina bentsholongwane, ukuvavanya kokuqukethwe kweqanda lomntwana. Ukusetyenziswa kwezixhobo eziphezulu zokusombulula i-ultrasound kuvumela ukuqeda ukuphulwa okunjalo njenge-anembrionia, xa umbungu ungekho.