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O Período Embrionário (As Primeiras 8 Semanas)
Desenvolvimento Embrionário: As Primeiras 4 Semanas
Capítulo 3 Fertilização
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| Ngokwemithetho yempilo,
"ukukhula komuntu
kuqala ekukhulelweni,"
uma owesilisa nowesifazane
emunye efaka 23
wama-chromosomes abo
ngokuhlangana
kwamaseli abo enzalo.
Iseli yenzalo yowesimame
kuthiwa yi"qanda"
kodwa igama eliyilo yi-oocyte.
Ngokunjalo, iseli
yenzalo yowesilisa
kuthiwa yi"mbewu"
kodwa kungcono uma
kuthiwa yi-spermatozoon.
Emva kokukhishwa kweqanda
esizalweni sowesimame
ngohlelo okuthiwa yi-ovulation,
iqanda nembewu
kuyahlangana
kwelinye lamashubhu
esibeletho,
avame ukubizwa
ngama-Fallopian tubes.
La mashubhu ahlanganisa
isizalo sowesimame
nesibeletho sakhe.
Umbungu owumphumela
kuthiwa yi-zygote,
okuwukuthi "kuhlangene."
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Capítulo 4 DNA, divisão celular e Fator Inicial da Gravidez (EPF)
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| Ama-chromosomes e-zygote awu 46
amele
ingxenye yokuqala
yesifanekiso sofuzo
somuntu omusha.
Le sakhiwo sihlala
kumamolikuli athothene
okuthiwa yi-DNA.
Inemiyalelo
yokukhula
komzimba wonke.
Amamolikuli e-DNA
anjengesikhwelo esisontekile
okwaziwa njenge-double helix.
Amaqophelo esikhwelo enziwe
ngamamolikuli angamabili,
okuthiwa yi-guanine,
cytosine, adenine, ne-thymine.
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| I-guanine ihambisana
kuphela ne-cytosine,
i-adenine ihambisane ne-thymine.
Iseli ngalinye lomuntu
cishe libe no 3 billion
wala mapheya ayiziqu.
I-DNA yeseli elilodwa
inolwazi oluningi kangangoba
uma lungahle lubhalwe
ngamagama,
ukuhlela igama lokuqala
lesiqu ngasinye
kungadinga amakhasi
angaphezu kuka 1.5 million!
Uma ilandelaniswa,
iDNA kwiseli lomuntu elilodwa
ikaleka ibewu 3 1/3 amafidi
noma 1 imitha.
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| Uma singayiqaqa
yonke iDNA
ekumaseli omuntu
angu 100 trillion,
ingaba ngaphezu
kwamamayela angu 63 billion.
Le libanga lifika
elangeni libuye
izikhathi eziwu 340.
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| Cishe emahoreni awu 24 kuyaku
30 emva kokukhulelwa,
i-zygote iqeda ukuhlukaniseka
kwamaseli kokuqala.
Ngohlelo lwe-mitosis,
iseli lihlukaniseka kabili,
amabili abe mane, njalonjalo.
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| Emva kuka 24 kuyaku 48 amahora
ukukhulelwa kuqalile,
kungaqinisekiswa
ngokuthola ihomoni
okuthiwa "wuphawu lokuqala "
egazini likamama.
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Capítulo 5 Estágios Iniciais (Mórula e Blastocisto) e Células Tronco
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| Ngosuku luka 3 kuyaku 4
emva kokukhulelwa,
amaseli andayo ombungu
aba sandilinga
bese umbungu
kuthiwa yi-morula.
Ngosuku luka 4 noma 5, kwakheka
umgodi kule libhola lamaseli
bese umbungu
kuthiwa yi-blastocyst.
Amaseli ngaphakathi
kwi-blastocyst
kuthiwa yinqwaba yamaseli
angaphakathi
kanti akha ikhanda, umzimba,
nezinye izakhiwo
ezisemqoka kumuntu okhulayo.
Amaseli angaphakathi
kule nqwaba yamaseli
kuthiwa ama-embryonic stem
cells ngoba akwazi
ukwakha inhlobo ngayinye
yamaseli kwezingaphezu kuka 200
asemzimbeni womuntu.
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Capítulo 6 1 a 1½ Semanas: Implantação e Gonadotrofina Coriônica Humana (hCG)
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| Emva kokwehla
ngeshubhu lesibeletho,
umbungu wokuqala
uzishutheka
odongeni olungaphakathi
lwesibeletho sikamama.
Lo luhlelo, okuthiwa wukuzihloma,
luqala emva kuka 6 izinsuku
luphele emva kuka 10 kuyaku 12
izinsuku emva kokukhulelwa.
Amaseli ombungu okhulayo
aqala ukukhiqiza ihomoni
okuthiwa yi-human chorionic
gonadotropin, noma hCG,
etholwa yiningi
lokuhlolela ukukhulelwa.
I-HCG itshela amahomoni owesimame
ukuthi akuyekise ukuya
esikhathini okuvamile,
okuvumela ukukhulelwa kuqhubeke.
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Capítulo 7 A Placenta e o Cordão Umbilical
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| Emva kokuzihloma,
amaseli azungeze
i-blastocyst
akha ingxenye yalokho
okuthiwa yi-placenta,
ewukuxhumana phakathi
kohlelo lukamama
nolombungu lokugeleza kwegazi.
I-placenta ihambisa
i-oksijini, izakhamzimba,
amahomoni, nemithi kukamama
embungwini okhulayo;
isusa wonke udoti;
bese ivimba ukuxubana
kwegazi likamama
nelombungu nele-fetus.
I-placenta ibuye
Ikhiqize amahomoni
ibuye igcine izinga lokushisa
lomzimba wombungu
libe ngaphezudlwana
kwelikamama.
I-placenta ixhumana
nomuntu okhulayo
ngemithambo
yenkaba.
Amakhono enkaba okweseka impilo
e-placenta alingana nalawo
amagumbi abagula kakhulu
ezibhedlela zesimanje.
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Capítulo 8 Nutrição e Proteção
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| Ngeviki 1,
amaseli enqwaba yamaseli engaphakathi
akha izingqimba ezimbili okuthiwa
yi-hypoblast
ne-epiblast.
I-hypoblast yakha
i-yolk sac (isikhupahshi),
okungesinye sezakhiwo
okuthi ngaso
umama aphakele izakhamzimba
kumbungu wasekuqaleni.
Amaseli aphuma kwi-epiblast akha
ijwabu okuthiwa yi-amnion,
ngaphakathi embungwini
kamuva kwi-fetus
liyakhula kuze kube wukuzalwa.
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Capítulo 9 2 a 4 Semanas: Camadas Germinativas e Formação de Órgãos
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| Cishe ngo 2 1/2 amaviki,
i-epiblast seyakhe
3 amathishu ayisipesheli,
noma izingqimba zamagciwane,
okuthiwa yi-ectoderm,
endoderm,
ne-mesoderm.
I-ectoderm yakha
izakhiwo eziningi
kubandakanya ubucopho,
umgogodla,
imizwa,
isikhumba,
izinzipho,
nezinwele.
I-endoderm ikhiqiza untwentwesi
lomgudu wokuphefumula
nolomgudu wokugaywa kokudla,
bese yenza izingxenye
zezitho ezisemqoka
njengesibindi
namanyikwe.
I-mesoderm yakha inhliziyo,
izinso,
amathambo,
uqwanga,
imisipha,
amaseli egazi,
nezinye izakhiwo.
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| Emva kwamaviki awu 3
ubuchopho buhlukaniseka
ezingxenyeni zokuqala eziwu 3
okuthiwa wubuchopho baphambili,
ubuchopho obuphakathi,
nobuchopho obungemuva.
Ukukhula kwemigudu yokuphefumula
nowokugaywa kokudla
nako kuyaqhubeka.
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| Khathi amaseli okuqala egazi
evela kwi-yolk sac,
kwakheka imithambo yegazi
kuwowonke umbungu,
bese kuvela inhliziyo esashubhu.
Cishe ngokuphazima kweso,
inhliziyo ekhula ngamandla
iyazisonga
ngenkathi amakamelo ehlukene
eqala ukwakheka.
Inhliziyo iqala ukushaya
kumaviki awu 3 nosuku
emva kokukhulelwa.
Umgudu wegazi
wumgudu womzimba wokuqala,
noma iqembu lezitho ezihlobene,
oveza isimo sokusebenza.
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Capítulo 10 3 a 4 Semanas: O Dobramento do Embrião
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| Phakathi kuka 3 no 4 wamaviki,
isakhiwo somzimba siyavela
ngesikhathi ubuchopho,
umgogodla,
nenhliziyo kombungu
sekubonakala kalula
eceleni kwe-yolk sac.
Ukukhula ngamandla kudala ukusongeka
kombungu owendlalekile.
Lo luhlelo luhlanganisa
ingxenye ye-yolk sac
ontwentwesini
lomgudu wokugaya ukudla
bese lwakha imigodi
yesifuba nowesisu
yomuntu okhulayo.
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