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The Endowment for Human Development
The Endowment for Human Development
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Multilingual Illustrated DVD [Tutorial]

The Biology of Prenatal Development




IBHAYOLOJI YANGAPHAMBILI KOKUBELETHWA KOMNTWANA

.Ndebele [Sindebele (Ndebele)]


National Geographic Society This program is distributed in the U.S. and Canada by National Geographic and EHD. [learn more]

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Chapter 41   4 to 5 Months (16 to 20 Weeks): Stress Response, Vernix Caseosa, Circadian Rhythms

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.

Chapter 42   5 to 6 Months (20 to 24 Weeks): Responds to Sound; Hair and Skin; Age of Viability

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.