Ntau tus niam txiv yav tom ntej xav hais tias placenta thiab zais zis yog ib qho thiab tib yam. Qhov tseeb, qhov no tsis yog li ntawd. Lub placenta yog ib qho kev ywj pheej uas muab cov khoom noj thiab cov pa oxygen rau ntawm tus me nyuam hauv plab. Nws yog los ntawm nws hais tias fetus txuas nrog niam lub cev.
Qhov hnyuv hauv lub plab yog dab tsi?
Kev txhim kho ntawm cov hnub nyoog fetal pib tom qab cog kev cog lus . Yog li, amnion yog ib semitransparent membrane nyias, uas muaj yeej tseem zoo ntawm cov ntaub so ntswg thiab epithelial.
Ib qho kev chorion yog nyob ncaj nraim ntawm amnion thiab decidua. Nws muaj ntau cov hlab ntsha.
Daim duab ntawm lub plab yog nyob nruab nrab ntawm lub plab thiab ntawm lub plab me.
Lub ntsiab ntawm lub fetal zais zis yog nws ntom thiab loj, uas nws txawv ntawm lub lim tiam ntawm cev xeeb tub. Yog li, nyob rau 30th hnub, lub cheeb ntawm fetal zais zis yog 1 hli thiab ces nce los ntawm 1 mm ib hnub twg.
Dab tsi yog qhov hauj lwm ntawm lub plab zais zis?
- synthesis ntawm ntau yam tshuaj uas muab kev tiv thaiv kab mob;
- paraplacental roj pauv hloov (kev saib xyuas cov kua dej hauv amniotic kua);
- tso kua mis thiab huv si ntawm amniotic kua;
- tshem tawm cov khoom siv kab mob metabolic;
- kev tso tawm hormonal tshuaj uas ua rau kom muaj kev tu ncua ntawm cev xeeb tub;
- kev tiv thaiv (ceeb toom fetus ntawm tus kab mob thiab raug mob).