I-axial skeleton iyisici. Biology mayelana nemisebenzi yayo nencazelo

Imisebenzi yokusekela umzimba nokuvikela izitho zangaphakathi ezilwaneni zingenziwa ngezindlela ezimbili. Esikhathini sokuqala, i-squelette yangaphandle ikhiwa - igobolondo. Iqukethe i-chitin, ngoba amandla amakhulu afakwe amanoni e-calcium, i-phosphorus noma i-silicon. Ama-Crustaceans, izigaxe, izibungu, izinambuzane ziyizilwane ezine-shells futhi zibizwa ngokuthi ama-invertebrates. Elinye iqembu lezinyamazane ekusetshenzisweni kwe-embryogenesis lakha isifuba sangaphakathi, indima yayo idlala yi-chord.

I-biology ichaza ukubonakala kwayo ngenxa yenqubo ye-organogenis - ukwakheka kwesakhiwo esiyinkimbinkimbi sezinhlaka ze-axial. Ukuze ithwale i-tube yomshukela, isisu nomculo. Ukuvela kwe-strand ephathekayo ye-tissue strand esiteshini se-neurula se-embryo kuyisici esihlukile kokubili abantu nezilwane ezihlobo lwe-Chodovy. Ake sicabangele le nqubo ngokuningiliziwe, kanye nokucacisa indima ye- axial skeleton emzimbeni wama-vertebrates.

Iyini isici ku-biology?

Incazelo yalesi sigaba se-fetus yile ndlela elandelayo: yinkambo yomgogodla engahlanganisiwe ehlanganisa izicubu ezithintekayo. Kuyinto eyimpoqo embryogenesis yazo zonke izilwane zaseChordovye. Ukwakheka kwezinto zokugqoka kwenzeka ngaphansi kwebhubhisi le-neural elivela emkhatsini we-chordomesoderm, okuyi-derictative ye-ectoderm yomathumbu oyinhloko. Ngesikhathi i-organogenesis, iguqulwa ku-tube yamathumbu, etholakala ngaphansi kwe-chord. Izinqubo ezichazwe ngenhla ziyinkimbinkimbi futhi zifundiswa ngesikhathi se-biology jikelele esikoleni esiphakeme. Indlela yokuchazela abafundi abafunda esikoleni abasebasha befunda i-zoology ukuthi yisiphi isici? I-Biology (iBanga lesi-7) ibheka isakhiwo se-dorsal axis ngesakhiwo se-lancelet. Ake sihlale ngalolu daba ngokuningiliziwe.

Izimpawu ze-Subtype Cranial

Leli qembu elihleliwe liqukethe i-Class - Lancets eyodwa. Izilwane zihlala ngaphansi koLwandle Olumnyama, zichitha cishe yonke impilo yazo, zingcwatshwe esihlabathini futhi ziveze ubuso bokuphela komzimba, zizungezwe izintambo. Ngomzimba we-semitransparent, ithubhu elinyene, i-chord, ivela kuwo. I-Biology ibheka njengengxenye ebalulekile yesistimu yokuqoqa izilwane. Umthambo womgogodla we-lancelet, njengamanye amathintelo okuqala - isibani nesimonx, ezise-vertebrates ezingaphelele, zikhona kulo lonke i-ongenisis. Lenza njengama-axial skeleton. Ngaphezu kwezinto eziphilayo ze-skullless ne-cyclostomes, i-chord igcinwa kwezinye izinhlanzi. Ake sicabangele izici zesakhiwo sabo.

Izinhlanzi ezinomdlavuza

Ikati elwandle, i-fox yolwandle, i-fish-saw, i-katran ngamagama abantu abahlala emanzini aphansi: imisebe kanye noshaki. Isakhiwo senkxaso yabo kanye nesistimu yabo yokunyakaza kuhlanganisa isifuba nesifo semisipha. Phakathi kwezidumbu zama-vertebrae nasendlini yomthamo we-vertebral kukhona izingcezu ezisele zomcibisholo wobumvu. Lesi sici siyingxenye ehlukile yesakhiwo sangaphakathi sezinhlanzi ezinamazinyo, lapho ngisho ne-adult chord igcinwa kancane. I-biology ichaza lokhu ngale ndlela elandelayo: phakathi ne-embryogenesis, amafomu e-spinal e-distances elilingana komunye nomunye izimbangela lapho kusetshenzwa khona inqubo yokumiswa kwezinhlaka zokubala. Kancane kancane bahlukanisa i-chord emizimbeni ye-vertebrae yezintambo, futhi izingxenye zayo ezihlangene zihlala ngaphakathi kwama-disc intervertebral.

Izici zesakhiwo senhlanzi seSturgeon Series

Kanye noshaki nemisakazo, abanayo izici eziningi ezivamile, abamele leli qembu bangabanhlanzi basendulo. I-Sturgeon, i-beluga, i-sturgeon ye-stellate ibonakala ngezici ezinjalo zesakhiwo njenge-skeleton yangaphakathi ne-chorda. I-Biology ithi abakhokho be-sturgeon izinhlanzi babonakala esikhathini se-Devonian se-Paleozoic. Kusukela ngaleso sikhathi umkhuba wabo we-anatomy awuzange ushintshe. Amafomu amadala anencingo, ehlanganiswe ngendwangu yezicubu ezinomsoco futhi ehlala isikhathi eside. Umdwebo omile omile we-stellgeon stellate, i-sterlet kanye nezinye izidakamizwa zaseRussia sekuyisikhathi eside isetshenziselwa ukudla kokuphaya kanye ne-alebyak, ukuyibiza ngokuthi i-tie.