izinhlanzi zikhiqiza kanjani

Umlobi: Laura McKinney
Usuku Lokudalwa: 2 Epreli 2021
Ukuvuselela Usuku: 17 Unovemba 2024
Anonim
Uzonqoba kanjani
Ividiyo: Uzonqoba kanjani

-Delile

Ngesikhathi sokukhula kombungu kwanoma yisiphi isilwane, kwenziwa izinqubo ezibalulekile zokwakhiwa kwabantu abasha. Noma ikuphi ukwehluleka noma iphutha ngalesi sikhathi kungadala umonakalo omkhulu enzalweni, kufaka phakathi ukufa kwengane.

Ukukhula kombungu kwezinhlanzi kuyaziwa, ngenxa yokuthi amaqanda abo asobala futhi yonke inqubo ingabonakala ngaphandle usebenzisa izinsimbi ezifana nengilazi yokukhulisa. Kule ndatshana kaPeritoAnimal sizofundisa eminye imiqondo nge-embryology futhi, ikakhulukazi, mayelana ikhiqiza kanjani izinhlanzi: ukukhula kombungu.

Ukuthuthukiswa kombungu wezinhlanzi: imiqondo eyisisekelo

Ukuze sisondele ekukhuleni kombungu kwezinhlanzi, okokuqala kudingeka sazi imiqondo eyisisekelo ye-embryology, njengezinhlobo zamaqanda nezigaba ezakha ukukhula kombungu wokuqala.


Singathola okuhlukile izinhlobo zamaqanda, ngokusho kwendlela inkonyane (izinto ezinomsoco ezikhona eqandeni lezilwane eliqukethe amaprotheni, i-lectin ne-cholesterol) okusatshalaliswa nobuningi bayo. Okokuqala, ake sibize umphumela wokuhlangana kweqanda nesidoda njengeqanda, futhi njengenkonyane, isethi yezakhi zomzimba ezingaphakathi kweqanda futhi ezizosebenza njengokudla kombungu wesikhathi esizayo.

Izinhlobo zamaqanda ngokwenhlangano yethole ngaphakathi:

  • amaqanda ahlukanisiwe: ithole litholakala lisatshalaliswa ngokulinganayo kulo lonke ingaphakathi leqanda. Izilwane ezijwayelekile ze-poriferous, ama-cnidarians, ama-echinoderms, ama-nemertine nezilwane ezincelisayo.
  • amaqanda akhethwa kabushai-yolk isuswa endaweni eyiqanda, ibhekene nendawo lapho umbungu uzokhula khona. Izilwane eziningi zivela kulolu hlobo lwamaqanda, njengama-molluscs, izinhlanzi, izilwane eziphila ezweni nasemanzini, izilwane ezinwabuzelayo, izinyoni, njll.
  • Amaqanda ama-Centrolecitosi-yolk izungezwe yi-cytoplasm futhi lokhu kuzungeza i-nucleus ezokhipha umbungu. Kuvela kuma-arthropods.

Izinhlobo zamaqanda ngokwenani le-veal:

  • amaqanda oligolectics: mancane futhi anethole elincane.
  • amaqanda mesolocyte: Ubukhulu obuphakathi nenani elilinganisiwe le-veal.
  • amaqanda ama-macrolecite: angamaqanda amakhulu, ane-veal eningi.

Izigaba ezijwayelekile zokukhula kombungu

  • Ukuhlukaniswa: kulesi sigaba, kwenzeka uchungechunge lokuhlukaniswa kwamaseli okwandisa inani lamaseli adingekayo esigabeni sesibili. Iphelela esimweni esibizwa nge-blastula.
  • Ukukhipha isisu: kukhona ukuhlelwa kabusha kwamaseli we-blastula, okwenza ama-blastoderms (izingqimba zamagciwane akudala) okuyi-ectoderm, i-endoderm futhi, kwezinye izilwane, i-mesoderm.
  • Umehluko kanye ne-organogenesis: izicubu nezitho kuyokwakheka kusuka ezingqimbeni zamagciwane, kwakheke ukwakheka komuntu omusha.

Izala kanjani inhlanzi: ukukhula nokushisa

Izinga lokushisa lihlobene kakhulu nesikhathi sokufukamela kwamaqanda ezinhlanzini nokukhula kwawo embryon (kwenzeka okufanayo nakwezinye izinhlobo zezilwane). Imvamisa kunefayela le- elikhulu lokushisa ububanzi for incubation, eyehluka cishe ngo-8ºC.


Amaqanda afukanywe ngaphakathi kwalolu hlu azoba nethuba elikhulu lokukhula nokuchanyuselwa. Ngokunjalo, amaqanda afukanywe isikhathi eside emazingeni okushisa aqatha (ngaphandle kohlobo oluhle lwezinhlobo) azoba naphansi amathuba okuchanyuselwa futhi, uma zichanyuselwa, abantu abazalwe bangahlupheka anomalies ezimbi.

Ukuthuthukiswa kombungu wenhlanzi: izigaba

Manje njengoba usazi izisekelo ze-embryology, sizobheka ukukhula kombungu wezinhlanzi. izinhlanzi zikhona tabolectic, okungukuthi, zivela emaqandeni e-telolecite, lawo ane-yolk ayiswe endaweni yamaqanda.

Ezihlokweni ezilandelayo sizochaza kunjani ukukhiqizwa kwezinhlanzi.

Ikhiqiza kanjani izinhlanzi: isigaba se-zygotic

Iqanda elisanda kukhulelwa lihlala ku- isimo se-zygote kuze kufike esigabeni sokuqala. Isikhathi esilinganiselwe lesi sigaba senzeka sincike ezinhlotsheni nasezingeni lokushisa kwemvelo. Inhlanzi yedube, UDanio rerio (inhlanzi esetshenziswe kakhulu ocwaningweni), ukwahlukaniswa kokuqala kwenzeka nxazonke Imizuzu engama-40 ngemuva kokukhulelwa. Yize kubonakala sengathi ngalesi sikhathi akukho zinguquko, ngaphakathi kwezinqubo ezinqumayo zamaqanda zokuqhubeka okuqhubekayo ziyenzeka.


Hlangana: Izinhlanzi eziphefumula ngamanzi

Ukukhiqizwa kwezinhlanzi: isigaba sokuhlukaniswa

Iqanda lingena esigabeni sokuhlukaniswa lapho ukuhlukaniswa kokuqala kwe-zygote kwenzeka. Ezinhlanzini, ukwahlukaniswa kunjalo meroblastic, ngoba ukwahlukana akuweli ngokuphelele iqanda, njengoba kuvinjelwa isikhuphasha, kukhawulwa endaweni lapho umbungu utholakala khona. Izigaba zokuqala zimile futhi zivundlile kumbungu, futhi zishesha kakhulu futhi zivumelanisiwe. Zibangela inqwaba yamaseli afakwe enkonyane, akha i- discoidal blastula.

Ukukhiqizwa kwezinhlanzi: isigaba sokugaya

Ngesikhathi sesigaba sokugaya, ukuhlelwa kabusha kwamaseli we-discoidal blastula kwenzeka ngo- ukunyakaza kwe-morphogenetic, okungukuthi, ulwazi oluqukethwe ku-nuclei yamaseli ahlukene asevele akhiwe, lubhalwa ngendlela ephoqa amaseli ukuthi athole ukumiswa okusha kwendawo. Endabeni yezinhlanzi, lokhu kuhlelwa kabusha kubizwa ukuzibandakanya. Ngokunjalo, lesi sigaba sibonakala ngokwehla kwezinga lokuhlukaniswa kwamaseli nokukhula okuncane noma okungekho kwamangqamuzana.

Ngesikhathi sokuzibandakanya, amanye amaseli we-discoblastula noma i-discoidal blastula afudukela esikhunjini, akha ungqimba phezu kwawo. Lesi sendlalelo kuzoba yi endoderm. Ungqimba lwamaseli ahlala enqwabeni luzokwakha i- ectoderm. Ekupheleni kwenqubo, i-gastrula izocaciswa noma, uma kuyinhlanzi, i-discogastrula, enezingqimba zayo ezimbili zamagciwane noma ama-blastoderms, i-ectoderm ne-endoderm.

Yazi kabanzi mayelana: izinhlanzi zamanzi anosawoti

Ukukhiqizwa kwezinhlanzi: umehluko kanye nesigaba se-organogenesis

Ngesikhathi sokuhlukaniswa kwezinhlanzi, kuvela ungqimba lwesithathu lwembungu, oluphakathi kwe-endoderm ne-ectoderm, olubizwa ngokuthi mesoderm.

I-endoderm invaginates yakha umgodi obizwa ngokuthi archentor. Kuzobizwa umnyango wale ndawo blastopore futhi kuzoholela endunu yenhlanzi. Ukusuka kuleli phuzu, singahlukanisa i- isikhumba se-cephalic (ubuchopho ngokwakheka) futhi, ezinhlangothini zombili, i- ama-vesicles abonakalayo (amehlo esizayo). Ngemuva kwesikhumba se-cephalic, i- ishubhu le-neural yakha futhi, ezinhlangothini zombili, ama-somites, izakhiwo ezizogcina zakha amathambo omgogodla nezimbambo, imisipha nezinye izitho.

Ngalesi sigaba, ungqimba ngalunye lwegciwane luzogcina lukhiqiza izitho noma izicubu eziningana, ukuze:

ectoderm:

  • I-Epidermis nesistimu yezinzwa;
  • Ukuqala nokuphela kwendlela yokugaya ukudla.

mesoderm:

  • UDermis;
  • Izitho zemisipha, zokukhipha nokuzala;
  • I-Celoma, i-peritoneum nohlelo lokujikeleza kwegazi.

endoderm:

  • Izitho ezibandakanyeka ekugayeni: i-epithelium yangaphakathi yomgudu wokugaya kanye nezindlala ze-adnexal;
  • Izinhlaka eziphethe ukushintshaniswa kwegesi.

Funda futhi: Ukuzala Izinhlanzi ZaseBetta

Uma ufuna ukufunda izindatshana eziningi ezifana ne- izinhlanzi zikhiqiza kanjani, sincoma ukuthi ufake isigaba sethu se-Curiosities somhlaba wezilwane.