Lokhu kwenzeka kanjani?
Ngokokuqala ngqa, isazi saseJalimane uShpeman senza ucwaningo olwamvumela inqubo enjalo ukuba itholakale. Kulesi simo, njengezinto eziphilayo zokuhlola, wasebenzisa imibungu yama-amphibian. Ukuze ulandele izinguquko kumadayimics, usosayensi wasebenzisa izinhlobo ezimbili zama-amphibians: ikhefu le-Triton kanye nemigqa ye-Triton. Amaqanda ama-amphibian yokuqala asemhlophe, ngoba ayinayo i-pigment, kanti eyesibili ine-hue ephuzi eliphuzi.
Enye yezilinganiso ezenziwe kwenziwa kanje. Umcwaningi uthathe ucezu lombungu ovela endaweni yakhe ye-blastopore, ekhona esiteshini se-gastrula se-triton ye-comb futhi wayifaka emkhakheni we-gastrula we-newt striptum.
Endaweni lapho ukufakelwa khona kwenzelwa khona, i-tube neriber, i-chord kanye nezinye izitho ze-axial zezinto eziphilayo ezizayo zakhiwa ngemva kwesikhashana. Kulesi simo, ukuthuthukiswa kungafinyeleleka kulawo mazinga lapho umbungu owengeziwe ukhiwa ohlangothini lwe-lateral of the embryo lapho kudluliselwa khona izicubu, i E. umamukeli. Ngesikhathi esifanayo, i-embryo eyengeziwe ihlanganisa amangqamuzana atholakele, noma kunjalo, amaseli emibungu e-embryo anemibala ekhanyayo atholakala ezingxenyeni ezihlukene zomzimba womamukeli.
Kamuva lesi simo sasibizwa ngokuthi ukufakwa kokuqala kwamabriyoni.
Iyini ukubaluleka okuyinhloko kokungeniswa kwe-embryonic?
Kusukela ekuhlangenwe nakho okungenhla, iziphetho eziningana zingadonselwa.
Ngakho okokuqala kuhilela ukuthi isayithi esithathwe emlonyeni we-blastopore unamandla okuqondisa ukuthuthukiswa kwezinto ezitholakala ngokushesha. Ngamanye amazwi, ngamanye amazwi, kubangela, njengokungathi. uhlela ukuthuthukiswa kombungu kokubili endaweni evamile nasezindaweni ezisezingeni eliphezulu.
Okwesibili, zombili izinhlangothi ezingezansi ze-gastrula zinamathuba amaningi, okufakazela ukuthi esikhundleni somzimba ovamile, ngaphansi kwemibandela yokuhlolwa, i-embryu yonke, yesibili ivela.
Okwesithathu, isakhiwo esiqondile samalungu asanda kwakhiwa esakhiweni sokufakelwa kabusha siphinde sibonise ukuba khona komthethonqubo we-embryonic. Lesi sici sigcwaliseka ngenxa yobuqotho bomzimba.
Yiziphi izinhlobo zokufakelwa kwamabrikhi ezikhona?
Emuva ema-30s ekhulwini lama-20, abacwaningi baqhuba ucwaningo olwamvumela ukucacisa uhlobo lwesenzo sokunciphisa. Ngenxa yalokho, kutholakala ukuthi amakhemikhali ngamakhemikhali ahlukene njengamaprotheni, ama-steroids, ama-nucleoproteins, akwazi ukufaka induction. Yile ndlela isimo samakhemikhali sabahleli bezinqubo zokungeniswa esungulwe.
Ngaphandle kweqiniso lokuthi abahleli benkambiso basungulwa, kwenzeka ukuthi inqubo ngokwayo ingaba nezinhlobo ezithile.
Ngakho-ke, kungaphethelwa ukuthi isimo se-induction embryo sibonisa ukuthi kungenzeka ukuthi izingxenye zombungu ngamunye zizimele. Ngamanye amazwi, ukufaka isiqephu sesisindo kusuka kwesinye embungu, ngokusemandleni kungenakuthola kuphela ingxenye noma isilwane esithile, kodwa futhi yonke imvelo, engafani nomamukeli. Yingakho into efana ne-embryonic induction kanye nokubaluleka kwayo ibaluleke kakhulu kumuthi wokubuka umbono.