Nhasi tiri kuzotaura pamusoro zvikuru zvinokosha organelle mumhuka. Zvayo nezve blastopore. Blastopore inonzi kuvhurwa kwedanda remuti weArchenteron. Iyi archenteron ndiyo embryonic mhango iyo inoumba blastula uye iri kusangana nevekunze. Kukosha kweblastopore kunogara mukuti nekuda kwayo muromo uye anus yemhuka zvinoumbwa.
Naizvozvo, isu tichaenda kukuudza zvese zvaunoda kuti uzive nezve blastopore, hunhu uye kukosha kwayo.
Chii chinonzi blastopore
Ndiwo mukova unobuda mukanwa neanus yemhuka. Munguva yekuumbwa kwe "embryo", matatu embryonic germ maseru anokura anozivikanwa se ectoderm, mesoderm uye endoderm. Maitiro ekuumbwa kwe "embryo" anozivikanwa nezita rekuti gastrulation. Maseru evanhu vane epiblastic vanotama kubva padanda remuti kuenda padanda remhuka. Iko kuri mukutama uku kuti ivo vanoumba blastula uyezve iwo akakosha matanda atataura. Kuonekwa kana kwete kwe arquénteron uye blastopore zvinoenderana zvachose nerudzi rwe blastula uye maitiro e gastrulation.
Kana kufamba kwacho kuchinge kuri kwekufungidzira, maseru ari muepiblast uye hypoblast anoenda kune yakazara mhango. Iyi mhango inozivikanwa nezita re blastocele. Ndipo ipapo panowanikwa nzvimbo nyowani yemhango mumuviri kugadzira archenteron, iyo inozozvarwa kubva muura. Icho chiri muchimiro ichi umo blastopore inoumbwa uye kune yayo yakatarisana nedivi muromo wemuromo.
Evhangeri uye kusimudzira
Mhuka dzakashanduka kubva munhoroondo uye dzakagadzira zvinowedzera kukura kuti zvikwanise kurarama munzvimbo dzakasiyana. Chikamu cheHoloblastic chinogadzira kubva ectodermal maseru iyo wechipiri embryonic layer inozivikanwa se endoderm. Rukoko rwakadzika kwazvo rwunokanganisa nzira yekugaya yekudya yemhuka ndiyo yakaiswa pakati pe ectoderm ne endoderm. Apa ndipo panowanikwa mesoderm.
Iwe unofanirwa zvakare kuziva kuti kune mhuka dzebhaibheri dzinongova nemaviri embryonic akaturikidzana. Kazhinji ndiyo mhuka dzakareruka senge chipanji. Iko kuumbwa kwegoridhe kweblastopore yezvipenyu zveumambo kunoenderana neyakagadziriswa trilaminar embryo. Iyo blastopore inogona kuzivikanwa zviri nyore nyore mu cnidarians. Uku kuumbwa kunoitika mushure mekuumbwa kweblastula. Inogona kukura nekufungidzira kana embolism.
Kana gastrulation ichiitika neepibolia, iyo blastopore inogadzirwa padanda rekudyara. Ndipo apo masero ari mudanda remhuka anotanga kuwanda zvakanyanya. Vanozviita nenzira yekuti vanokwanisa kukumbundira yolk macromers. Kana iyo nzira yekuzvarwa kwematanho embryonic ichiitwa nekusabatika, maviri chete embryonic akaturikidzana anoumbwa. Pano pindai boka remhuka dzatataura dzinodaidzwa kuti diblastics dzinongova neododerm neectoderm.
MaCnidarian anowira muboka revadzidzi. Nekuda kwe delamination kana kupinza, iyo blastopore haina kugadzirwa. Ichokwadi chekuti mitotic kupatsanurana kunoitika pakutanga kwemwana "embryo" kunoenderana neuwandu hwezvinhu zvinovaka muviri zvirimo mukadzi hutachiona hutachiona hunopa zizi rinozivikanwa seoocyte.
Basa uye kukosha kwe blastopore
Tichaenda kunongedzera chiri chakakosha basa iro iro blastopore rine mune zvipenyu. Ivo vanoumbwa kana ivo vari mumatanho ekutanga ekuvandudza kweiyo muviri. Hechino chikamu chegastrulation apo kupatsanurwa kwesero kunotanga. Ino zadzisa basa rekusagadzikana kumusana kweiyo embryo uye kuve wepakutanga murongi. Basa iro ine blastopore inogona kutaurwa mumuromo mezvipuka zvakadai semollusks, mhuka dzinokambaira, zvinokambaira uye shiri.
Kune rimwe divi, mune deuterostomous mhuka blastopore inotanga kukurudzira kuumbwa kweanus uyezve muromo. Mukupedzisira, iwo marongero anosiyana kana iwo ma protostomes kana deuterostomes. Blastopore inoitisa kutaurirana embryonic mhango nenyika yekunze. Kubva pamhedzisiro ye blastopore, bilateral kana triblastic zvipenyu zvinogona kuverengerwa aine chokwadi chikuru. Isu tinorangarira kuti ma triblastics ndiwo iwo akapunyuka akati wandei muVienna: ectoderm, endoderm uye mesoderm. Nenzira yetsika, mhuka idzi dzakaiswa mumapoka zvinoenderana nekuvapo kana kusavapo kwemakomba akazara mumuviri wese. Mune ino kesi, isu tinoona iyo yakakwenenzverwa, ichitonhodzwa yatove coelomed.
Kazhinji ma protostomes anosiyaniswa kuita maviri makuru anova iwo Ecdisozoa uye Lofotrocozoa. Iwo ekutanga ndeaya anogara achidurura akacheka-cheka uye ekupedzisira anozivikanwa nematombo e trochophore.
Iyo ramangwana re blastopore zvinoenderana nekubatana kwematumbu embryonic. Panyaya yemamphibian, muromo wekuputika we blastopore unoonekwa uye zvinobva kwazviri kuti zviratidzo zvese zvinotumirwa kumaseru matsva. Muboka remhuka dzakakurumbira muromo unotanga kubva kudivi rakatarisana ne blastopore. Kune rimwe divi, mune deuterostome mutsara, muromo unobva pane yechipiri kuvhura mushure mekuvandudza.
Protostomes uye deuterostomes
Kuvhura mune archwire kunova muromo mune protostomates uye anus mune deuterostomes. Ose maviri magumo enzira yekugaya. Iyo segmentation yeiyi chubhu inoumba iyo coelom uye iyo ramangwana re blastopore ndiyo iyo inoratidza kukura kwemhuka uye chimiro chavo. Mune protostomes chidimbu chechubhu chinotenderera uye mune deuterostomes iri indeterminate radial. Izvi zvakare zvine chekuita nekuenzanisa kweiyo muviri. Mukuyanana kwenyika mbiri tinowana muviri une zvikamu zviviri zvakafanana zvemuviri.
Mune mhuka dzakasimukira iyo coelom inoumbwa nekukamurwa kwemasimba akasimba emesoderm. Iyo mesoderm inozivikanwawo nezita rekuti schizocelia. Mumaviri ayo anokura nekuwedzeredzwa kweye archinteron panguva yekukura kwembryonic yemuviri.
Muboka remaprotostomes tinowana nematodes uye arthropods, mollusks, annelids uye flatworms. Echinoderms senge nyeredzi uye urchin yegungwa ndiwo deuterostomes.
Ndinovimba kuti neruzivo urwu unogona kudzidza zvakawanda nezve blastoporo nebasa rayo.