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DVD Ilustrado Multilíngue

The Biology of Prenatal Development




IBHAYOLOJI YANGAPHAMBILI KOKUBELETHWA KOMNTWANA

.Ndebele [Sindebele (Ndebele)]


 

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Capítulo 41   4 a 5 Meses (16 a 20 Semanas): Resposta ao Estresse, Verniz Caseoso, Ritmos Circadianos

Eemvekeni ezi-16, ikambiso yokufakwa kwenalithi ngemathunjini we-fetus aletha ukukhathazeka kwamahomoni kukhiphe i-noradrenaline, noma i-norepinephrine,iyithululele ngaphakathi kweengazi. Abentwana abancani nabantu abadala babonisa ipendulo efanako kukambiso yokungenelelwa.

Kuhlelo lokuphefumula, isitho esibizwa nge-bronchial tree sesicishe siphelele.

Into emhlophe evikelako, ebizwa nge-vernix caseosa, seyivale i-fetus. I-Vernix ivikela isikhumba ukuthi singahlushwa zinkathazo ze-amniotic fluid.

Ukusukela eemvekeni ezi-19 ukusikinyeka kwe-fetus,ukuphefumula kwayo, nokubetha kwehliziyo kuthoma ukulandela ihlelo elithileko elibizwa nge-circadian rhythms.

Capítulo 42   6 a 7 Meses (24 a 28 Semanas): Reflexo Cócleo-Palpebral e de Sobressalto; Pupilas Respondem à Luz; Olfato e Paladar

EEMVEKENI EZI-20 indlebe yangaphakathi (cochlea), okusisitho sokuzwa, seyikhule njengeyomuntu omdala ngaphakathi kwendlebe ekhulileko ngaphakathi. Kusukela nje ukuya phambalil, i-fetus izakuphendula imidumo eminengi ngokuya kwesikhathi.

Izinwele zicala ukukhula ekhanda.

Koke ukwakheka kwesikhumba kukhona, kufake hlangana imbotshana yezinwele,nama-glands.

Eemvekeni ezi-21 ukuya kwe-22 Ngemva kokumumatha, amaphaphu athola ithuba lokuphefumula umoya. Lokhu kwaziwa ngokwazi ukuphila(viability) ngoba ukuphila ngaphandle kwesibeletho kuyazakala kwamanye ama-fetuses. Ukuphumelela okunengi Kwemithi elaphako kwenza kwenzakale ukuqhubela phambili impilo kulabo abazalwe ngaphambili kwesikhathi.