Amphioxus circulatory system: cov yam ntxwv nta

Nyob rau lub Sandy seabed ua demersal txoj kev ua neej, dawb dawb thiab xim mis dawb los yog me ntsis pinkish translucent tsiaj hu ua Amphioxus. Lawv ntau thiab tsawg pab - los ntawm 5 mus txog 8 cm lub cev yog flattened laterally, pem hauv ntej thaum xaus ntawm nws obliquely txiav, thiab nws yog nws lub qhov ncauj, framed los ntawm tentacles .. Lub rear ib feem ntawm lub cev muaj hauv daim ntawv ntawm cov kev phais riam - Lancet. Tej seemingly inconspicuous tsiaj comparative lub cev thiab kev kawm txog tsiaj txhu kawm tiag rau ib tug yog vim li cas: Amphioxus nrhiav ib qhov txuas ntawm ob loj pawg ntawm cov tsiaj - invertebrates thiab chordates.

Nyob rau hauv no tsab xov xwm peb muab piv rau cov qauv ntawm Amphioxus nrog bony ntses, raws li zoo raws li muab ib lo lus teb rau hauv qab no lo lus nug: dab tsi yog qhov circulatory system nyob rau hauv Amphioxus? Lavxias teb sab biologist A. O. Kovalevsky nyob rau hauv 1860 muaj pov thawj hais tias cov tsiaj muaj zoo sib xws rau vertebrates, tswj tej yam tshwm sim ntawm invertebrate kab mob.

kev

Xav txog cov qauv ntawm cov circulatory system ntawm Amphioxus. Liab kua, uas tsis muaj xim, tsiv raws plab aorta, uas yog lossi pulsating lus vim myoepithelial txheej coelom kab noj hniav. Ces cov ntshav uas muaj ib tug dhau heev lawm ntawm cov pa roj carbon dioxide tau txais mus rau hauv lub taub hau ntawm lub Amphioxus. Lub branchial hlab ntsha nkev pauv tshwm sim. Leeg txaus rau hauv lub posterior lub caj pas sib cais, qhov twg ntawm txoj cai thiab sab laug feem ntawm lub dorsal aorta. Amphioxus lub cev pem hauv ntej ib feem muab nrog cov ntshav los ntawm cov carotid leeg tawm los ntawm lub aorta. Mus rau hauv me me arterioles oxygen-nplua nuj ntshav ntws rau tag nrho cov kabmob ntawm cov tsiaj. Lub venous ib feem ntawm lub cev pib network plab hnyuv venules muaj carbon dioxide. Ntawm no, cov ntshav nkag mus rau hauv cov hlab ntsha podkishechnuyu.

Muaj tsim lub portal system ntawm lub siab. Anatomically, nws yog nyob rau hauv lub plab hnyuv raj Amphioxus, decomposing rau hauv ib lub network ntawm venules, uas entwine lub phab ntsa ntawm lub digestive system. Nws muaj nuj nqi yog mus rau cov hloov lub lim toxins los ntawm cov ntshav muaj lub siab cov ntsiab lus ntawm cov pa roj carbon dioxide ntxiv nyob rau hauv lub venous qhov ntswg. Ntawm ob sab ntawm Amphioxus lub cev yog xa mus rau lub cardinal (aka jugular) cov hlab ntsha, ces Cuvier ducts.

Cuvier ducts

Cov leeg vertebrates thawj cais lancelet thiab tsim nyob lub hlws ris ntawm Cardinal hlab ntsha. Lawv liab kua los ntawm lub hauv pem hauv ntej thiab nram qab lub xaus ntawm tus tsiaj lub cev. Cuvier ducts ncaj qha ntws mus rau hauv lub qhov ntswg venosus, uas yog suav hais tias yog thaum pib ntawm lub plab aorta. Cov hlab ntsha kom meej meej qhia nyob rau hauv embryonic vertebrates, thiab nyob rau hauv post-embryonic lub sij hawm xam qhovkev cyclostomes (lamprey thiab hagfish), raws li zoo raws li ntses thiab amphibians. Qhov loj tshaj zoo sib xws yog cov circulatory system ntawm Amphioxus thiab cyclostomes, txawm hais tias tus tom kawg nkaus li tiag tiag lub plawv, muaj raws ntawm atrial thiab ventricular.

qhov ntswg venosus

Nws yog thawj ib feem ntawm lub plab aorta, thiab Amphioxus xws system yog ib tug raug kaw voj voog. Yog li, cov qauv ntawm cov circulatory system Amphioxus proves hais tias nws cov ntshav ncig yog kaw. Nyob rau hauv cov tsiaj, noog thiab lwm yam vertebrates, qhov no yog ib feem ntawm cov tub ceev xwm hais txog txoj cai atrium. Los ntawm nws lub venous kua nkag mus rau hauv ventricle thiab mus rau hauv lub pulmonary leeg. Yog li ntawd pib lub pulmonary ncig nyob rau hauv cov kab mob muaj ib tug plaub-chambered lub plawv. Nyob rau hauv Amphioxus, raws li zoo li lwm yam neeg sawv cev golovohordovyh lub plawv ploj lawm thiab venous qhov ntswg hais unpaired txog ntsha mus rau hauv uas lub venous kua los ntawm lub hepatic cov hlab ntsha. Tom qab ntawd nws nkag mus rau hauv lub plab aorta. Yog hais tias koj nco ntsoov cov qauv ntawm cov circulatory system ntawm Amphioxus thiab bony fishes, koj yuav pom tau tias cov kev hloov tau feem ntau cov mob plab aorta, uas yog hloov ntses nyob rau hauv lub ob-chambered lub plawv. Nyob rau hauv tas li ntawd, lub ua pa nto gills ntawm bony fishes kuj nce vim lub branching capillary network lawv ntses chaw dim pa hlab ntsha.

Rooj vag tshuab hepatic outgrowth

Amphioxus circulatory system, raws li zoo li lwm yam vertebrates, anatomically kev cob cog rua nrog lub digestive kabmob. Digestive tag nrho vertebrate tsiaj yog morphologically yam, thiab cov khoom ntawm dissimilation: qabzib, amino acids - tuaj mus rau hauv nws cov hlab ntsha. Ntxiv mus kawm cov qauv ntawm cov circulatory system ntawm Amphioxus, ntxiv hais tias tag nrho cov ntawm cov kua los ntawm tus tsiaj lub digestive apparatus nkag mus rau hauv hepatic outgrowth. Ib yam li ntawd, lub siab ntawm ntses, amphibians thiab lwm yam vertebrates, Amphioxus no lub cev ua cov kev ua ntawm detoxification, ntxuav cov ntshav los ntawm cov hnyuv ntawm cov hniav lwj khoom - metabolites. Nws ces nkag mus rau hauv qhov ntswg venosus. Ntxiv ntawd mus rau lub siab outgrowth ntawm cov ntshav tau txais podkishechnoy leeg.

Ventral thiab dorsal aorta

Nws yog ib tug tseem ceeb arterial txog ntsha. Yog hais tias koj nco ntsoov cov qauv ntawm cov circulatory system ntawm Amphioxus, koj yuav pom nyob rau hauv lub slides uas nyob rau hauv lub caj pas ntawm cov tsiaj yog cov mob plab aorta, los ntawm uas nthuav kev symmetrically paired leeg. Lawv ceg tawm nyob rau hauv partitions ntses chaw dim pa kab noj hniav. Nraub aorta yog tsim thaum lub tsheb thaum xaus ntawm lub caj pas raws li ib tug tshwm sim ntawm lub merger nadzhabernyh cov hlab ntsha. Anatomically, nws yog ib tug chord thiab ncua mus rau rear kawg ntawm lub cev Amphioxus, branching rau ntawm cov hlab ntsha uas pub cov hauv nruab nrog cev ntawm cov tsiaj. Nyob rau hauv Amphioxus metabolites pom nyob rau hauv cov ntshav yog lim los ntawm tshwj xeeb hlab hu ua protenefridiyami. Los ntawm cov mob plab aorta rau lub cev kab noj hniav - ib tug tag nrho - haum arterial txog ntsha. Nws branched rau hauv capillary glomeruli. Los ntawm lawv phab ntsa, cov ntshav pom thiab toxins nyob rau hauv yaj daim ntawv nyob rau hauv protenefridii tau txais, ces nyob rau hauv mezonefralny ciav thiab ntxiv mus rau hauv lub cloaca.

Lub circulatory system ntawm Amphioxus thiab bony fishes

Xav txog qhov sib thooj thiab sib txawv nyob rau hauv cov qauv ntawm cov hlab plawv system superclass Bony ntses thiab Golovohordovye hom uas nws belongs lancelet. Ob pawg neeg ntawm cov tsiaj muaj tus tib ncig. Tab sis lub plawv ntawm lub Amphioxus yog tsis muaj, cov nuj nqi yuav siv sij hawm nyob rau ib feem ntawm lub plab aorta, uas yog txo nrog nqa ntses chaw dim pa hlab ntsha thiab ua rau cov ntshav khiav. Cov ntses muaj ib lub plawv, nws yog zoo li nyob rau hauv cyclostomes, ob-chamber (atrium thiab ventricle).

Cov tsim ntawm lub cev vim rau qhov ntau active metabolism. Lub plawv ntses nyob ze ntawm lub Isthmus arcs nyob rau hauv lub qis lub puab tsaig. Raws li peb tau pom los ntawm cov saum toj no cov lus tseeb, cov qauv ntawm cov circulatory system ntawm Amphioxus, kom ntseeg tau cov thauj ntawm cov pa thiab as-ham, nws txawv ntawm hais tias ntawm bony fishes.

Nta ntawm cov ntshav mov rau cov ntses chaw dim pa apparatus

Yog hais tias koj nco ntsoov cov qauv ntawm cov circulatory system ntawm Amphioxus, piv nws nrog rau cov bony fishes, koj yuav nrhiav tau txawv uas nphav cov ntshav mov rau cov ntses chaw dim pa apparatus. Nyob rau hauv qis sab ntawm lub caj pas nyob plab aorta. Los ntawm nws rau txhua khub ntses chaw dim pa arches haum cov hlab ntsha, uas nqa venous ntshav. Txo tus naj npawb ntawm partitions nyob rau hauv lub gills (lancelet 150 officers, thiab nyob rau hauv cov ntses 4 officers) yog piav qhia los ntau zog metabolism thiab ib qho kev nce nyob rau hauv tag nrho cov cheeb tsam ntawm lub capillary network nyob rau hauv cov neeg sawv cev bony fishes. Lancelet tau ntub txaus nws cov ntshav oxygen tsis tsuas yog los ntawm cov branchial leeg system, tab sis kuj ncaj roj diffusion ntawm daim tawv nqaij ces dag cov hlab ntsha.

carotid leeg

Yog hais tias koj sib piv cov ntshav system ntawm Amphioxus thiab bony fishes, koj yuav nrhiav tau txawv rau cov hlab ntsha, hu ua carotid cov hlab ntsha. Lawv yog cov arterial liab kua rau pem hauv ntej thaum xaus ntawm tus tsiaj lub cev. Nyob rau hauv bony ntses 4 officers ntawm ntses chaw dim pa hlab ntsha ntws mus rau hauv lub dorsal aorta, cov hauv paus hniav ntawm cov uas muaj sib cais carotid leeg. Nyob rau hauv Amphioxus tus xov tooj ntawm ntses chaw dim pa hlab ntsha ntau npaum li cas. Lawv muab lub paj hlwb nrog rau oxygen, uas yog ib tug extension ntawm lub neural raj thiab kev hloov mus rau hauv lub tuam tsev. Nws tswj lub reflex kev ua si ntawm cov tsiaj. Muab hlwb neurons nrog rau oxygen thiab as-ham tshwm sim vim branching ntawm lub carotid cov hlab ntsha nyob rau hauv lub capillary system. Raws li nws yog los khoom - metabolites ua txhua yam los ntawm cov leeg nyob rau hauv lub venous qhov ntswg.

Qhov tsab xov xwm tau kawm cov circulatory system thiab nta Amphioxus ncig nyob rau hauv golovohordovyh.