Multilingual Illustrated DVD [Tutorial]

Nawukhuluma ngekwebhayologi, "kwakheka kwemuntfu kucalisa ngekwakheka kwembewu," ngalesikhatsi indvodza nemfati bahlanganisa 23 ngamunye wemakhromozomu abo lokwenteka ngekuhlangana kwetinhlayiya tabo tekutala.

Inhlayiya yemfati yekutala ibitwa ngalokwetayelekile ngekutsi "licandza" kepha ligama lakhona lelifanele yi-usayithi.

Ngalokufanako, inhlayiya yendvodza yekutala yatiwa ngalokwetayelekile ngekutsi "budvodza" kepha ligama lelinconotekako lakhona yispemathozoni.

Ngemuva kwekutsi sekuphume i-usayithi esibeletfweni semfati lokwenteka ngendlela lebitwa ngekutsi kuphuma kwelicandza, i-usiyothi kanye nespemathozoni kuyahlangana ngekhatsi etfunjini linye lematfumbu esibeletfo, lekuvamise kubhekiswa kuwo njengemaFalophiyeni shubhu.

Ematfumbu esibeletfo achumanisa sibeletfo semfati neyutherasi kumbe sibeletfo.

I-emrbiyo lenenhlayiya yinye ledaleka lapho ibitwa ngekutsi yizayigothi, lokusho kutsi "lokuboshelwe kumbe lokuhlanganiswe ndzawonye."

Emakhromozomu la-46 ezayigothi amelele sigaba sekucala lesingakavami sesitfombe semfanekiso lophelele weluhlelo lwelufuto lwemuntfu lomusha. Loluhlelo lolukhulu lolu luhlala ngekhatsi etinhlayiyaneni letisongekile tacina letibitwa ngekutsi yi-DNA. Ticuketse telayeto letimayelana nekwakheka kwawo wonke umtimba.

Tinhlayiyana te-DNA tifana nesitebhisi lesishwilekile lesatiwa ngekutsi yi-double helix. Letenyuko talesitebhisi tentiwe ngetinhlayiyana letihamba ngatimbili, kumbe emabheyisi, labitwa ngekutsi yigwanayni, sayithosin, adenayni, ne-thaymin.

Igwanayni ihambisana ngakubili nesayithosin kuphela, kutsi i-adenayni yona ihambisane nethaymin. Leyo naleyo inhlayiya yemuntfu Icuketse cishe 3 wetigidzi tetigidzi talamabheyisi lahamba ngamabili.

I-DNA yenhlayiya yinye icuketse lwati lolunyenti kangangekutsi kube bekulwati lolubhalwe ngemagama, kubhala nje kuphela luhlu lweluhlavu lwekucala lwaleyo naleyo bheyisi bekutawudzinga ngetulu kwemakhasi lasigidzi netinkhulungawane letingemakhulu lasihlanu embhalo!

Nakube beyingandlalwa phansi ilandzelane, i-DNA lesenhlayiyeni yemuntfu yinye beyingalingana na-3 1/3 wemafidi kumbe 1 mitha.

Kube besingayelula yonkhe i-DNA lengekhatsi kwetinhlayiya letisemntfwini lomdzala letilikhulu lemathriliyoni, beyingaba libanga lelingetulu kwemamayela langemashumi lasitfupha nakutsatfu wemabhiliyoni. Leli libanga lelingangekusuka emhlabeni uye elangeni uphindze ubuye tikhatsi leti-340.

Cishe 24 kuye ku-30 wema-awa ngemuva kwekwakheka kwembewu yemuntfu, izayigothi iyacedza kwehlukaniseka kwekucala kwenhlayiya yayo. Ngendlela yechubo yemayithosis, inhlayiya yinye ichekeka ibe tinhlayiya timbili,timbili tichekeke tibe tine, njalonjalo.

Emuva le kusaphele 24 kuya ku 48 wema-awa kucalise kwakheka kwembewu yemuntfu, kungacinisekiswa kwekutsi umuntfu utetfwele ngekutsi kutfolakale ihomoni lebitwa ngekutsi "luphawu lwekucalisa kutetfwala" engatini yenina.

Ngemuva kwa-3 kuya ku-4 wemalanga kwakheke imbewu yemuntfu, tinhlayiya letichekeka emkhatsini te-embriyo tiba yindzingilita bese kutsi i-embriyo ibitwa ngekutsi yimorula.

Emalangeni la-4 kuya ku-5, kwakheka imbobo ngekhatsi kwendzingilita yetinhlayiya bese kutsi i-embriyo seyibitwa ngekutsi yiblastosist.

Tinhlayiya letingekhatsi kweblastosist tibitwa ngekutsi ngumhlambi wetinhlayiya tangekhatsi futsi ngito letakha inhloko, umtimba,kanye naletinye takhiwo letibalulekile emntfwini lowakhekako.

Tinhlayiya letingekhatsi kwemhlambi wetinhlayiya tangekhatsi tibitwa ngekutsi tinhlayiyasicu te-embriyo ngobe tiyakwati kwakha leyo naleyo yaletinhlobo tetinhlayiya letingetulu kwa-200 leticuketfwe ngumtimba wemuntfu.

Ngemuva kwekuhamba yehle ngelitfumbu lesibeletfo, i-embriyo leseyincane itinamatselisa emtsangaleni wangekhatsi wesibeletfo senina. Lenchubo lena, lebitwa ngekutsi kumila, icalisa ngemuva kwa-6 wemalanga ibuye iphele ngemuva kwa-10 kuya ku-12 wemalanga yakhekile imbewu yemuntfu.

Tinhlayiya te-embriyo lekhulako ticalisa kukhipha ihomoni lebitwa ngekutsi yikhoriyonikhi gonadothrophini yemuntfu,kumbe i-hCG, lekuyintfo leba khona kuletinyenti tinhlobo tekuhlola kutsi umuntfu utetfwele yini.

I-HCG itjela emahomoni latfolakala ebafatini kutsi atsikamete luhlelo wekuya esikhatsini tinyanga tonkhe ngalokwetayelekile, kuze kutetfwala kuchubeke.

Ngemuva kwekumila, tinhlayiya letile emaphetselweni eblastosisti tihlumisa incenye yesakhiwo lesibitwa ngekutsi yiplasentha, lekungiyo leba ngumchumanisi emkhatsini wetinhlelo temitsambo yengati tenina nete-embriyo.

Iplasentha iletsela umuntfu Lowakhekako i-oksijini, kudla, emahomoni, kanye nemutsi lokusuka kunina; ikhiphe konkhe lokulahliwe; futsi ivimbele kutsi ingati yenina ingahlangani nengati ye-embriyo nefithasi.

Iplasentha iphindze ikhicite emahomoni futsi igcine lizinga lekushisa kwemtimba we-embriyo nefithasi lisetudlwana kancane kunelenina.

Iplasentha ichumana nemuntfu lowakhekako ngemitsambo yenkhaba.

Emandla eplasenta ekuniketa Imphilo angafaniswa nemandla eligumbi lalabagula kakhulu lelitfolakala etibhedlela tesimanjealamuhla.

Evikini le-1, tinhlayiya tencumbi yetinhlayiya letingekhatsi takha tincwencwe timbili letibitwa ngekutsi yihayiphoblast kanye ne-ephiblast.

Ihayiphoblast yenta kutsi kumile sikhwama semtfubi welicandza, lekungilesinye setakhiwo lesenta kutsi unina akwati kuniketa i-embriyo leseyincane kudla

Tinhlayiya letiku-ephiblast takha inyama letsambile lebitwa ngekutsi yi-amniyoni, lapho i-embriyo, ngekuhamba kwesikhatsi kulandzele ifithasi, kutawukhulela khona aze umntfwana atalwe.

Ngesikhatsi cishe lesingu 2 1/2 wemaviki, i-ephiblast ibe seyakhe 3 weticubu letikhetsekile, kumbe tingogo tetimbewana, letibitwa ngekutsi yi-ekthodem, i-endodem, kanye nemesodem.

I-ectodem yenta kutsi kumile takhiwo letinyentana kufake ekhatsi ingcondvo, umgogodla, imiva, sikhumba, tingalo, kanye netinwele.

I-endodem ikhicita lucwecwe loluvalewendlalele umgudvu wekuphefumula kanye nemgudvu logaya kudla, futsi imilisa tincenye tetakhiwo letinkhulu temtimba letifana nesibindzi kanye nemalulu.

Imesodem yakha inhlitiyo, tinso, ematsambo, ikhathilegi, imisipha, tinhlayiya tengati, kanye naletinye takhiwo.

Emavikini la-3 ingcondvo iyehlukaniseka iba tigaba leti-3 letinkhulu letibitwa ngekutsi yingcondvo lesembili, ingcondvo lesemkhatsini, kanye nengcondvo lesemuva.

Kukhula kweluhlelo lwekuphefumula kanye neluhlelo lwekugaya kudla nako sekucalile.

Ngalesikhatsi tinhlayiya tengati tekucala tivela esikhwameni semtfubi welicandza, kwakheka imitsambno yengati kuyo yonkhe i-embriyo, futsi kucalisa nekubonakala inhlitiyo lemisiphasipha.

Masinyane emvakwaloko, inhlitiyo lekhula masinyane iyatisonga ivaleke ibe ngemagumbi lehlukene icalise kwakheka.

Inhlitiyo icalisa kushaya emavikini la-3 nelilanga linye ngemuva kwekwakheka kwembewu yemuntfu.

Luhlelo lwekuhamba kwengati luhlelo lwekucala lwemtimba, kumbe licembu letitfo temtimba letihambisanako, lolucalisa kusebenta.

Emkhatsini wemaviki la-3 nala-4, luhlelo lwemtimba lucalisa kubonakala ngalesikhatsi ingcondvo, umgogodla, kanye nenhlitiyo ye-embriyo sekubonakala kalula eceleni kwesikhwama semtfubi welicandza.

Lokukhula masinyane kubangela kutsi i-embryo lekungashiyo kutsi isicabati ivaleke. Lenchubo lena ifaka incenye yesikhwama semtfubi welicandza ngekhatsi elucwecweni lwemgudvu logaya kudla bese kwakheka sifuba kanye nendzawo yesisu kwalomuntfu lowakhekako.