Amphioxus - wukuthi isilwane? Amphioxus: incazelo, isakhiwo, izici kanye nezici

Amphioxus - isilwane ezihlobene uhlobo Chordates (iqembu bescherepnyh). Sikunikeza ukuba simazi naye. Sibheka isakhiwo, izici nezici Amphioxus. Lolu hlobo kutholakala ezilwandle izingxenye esipholile futhi ezishisayo. Ikakhulukazi, Amphioxus siphile futhi oLwandle Olumnyama.

komzimba

Amphioxus komzimba okusaqanda, tapering kuya umsila. Ubude ivela 4 kuya kwezingu-8 cm. Umzimba embozwe ungqimba elilodwa epithelium futhi cuticle ethakwa amangqamuzana EPITHELIAL. Ngezansi epithelium kuyinto ungqimba elincanyana sezicubu zezinzwa - corium. I amaphiko ohlangothini umzimba kanye nomsila fin ozungezwe isikhumba emhlanjini. Umzimba isicaba singatsheki; eceleni ventral elula abhanqiwe metaplevralnye emphethweni yokuxhuma undernail ingxenye nesibaya fin. Lesi sakhiwo kusiza kuqiniswa isikhundla umzimba ngamanzi kwandisa endaweni ukuxhumana ke, okuyinto ebaluleke lapho sidlula esonta umzimba.

uhlelo zemisipha

Ngesisekelo Uhlaka okuyinkomba kuzithinta esemgwaqweni umzimba kusukela ekhanda kuya ekupheleni esifundeni caudal. Kuzithinta, esesikhundleni lancelet - lokhu kumiswa ebiyelwe sikhwama zezinzwa, lapho izindlela ifomu asekelayo izakhi nesibaya fin kokuba amakholomu ifomu chondroid. Iphinde lingena phakathi izingxenye ngazinye ezicutshini (Myomere) ukwakha miosepty abahlukanise. Myomere ahlukaniswe mioseptami eyayiseduze kuzithinta nhlangothi zombili.

muscularity

imisipha Striated. Myomere Hlukanisa abe ukuma oyindilinga, sengathi kubuyiswe ku bebodwa kanye ilungiselelo yabo azilingani: okuphambene phakathi ngamunye wabo ohlangothini lwesokudla kuyinto miosepta ngakwesokunxele, noHezekeli. ukunciphisa Progressive kwemisipha ingxenye ohlangothini umzimba Curves, amagagasi ezihambayo kusukela ekhanda kuya umsila. uhlamvu Zemvelo imisipha kulawulwa isimiso sezinzwa esiyinhloko.

Amphioxus kuzithinta we front end ubabonisa kwalokho.-neural tube, kungakho igama layo liyi nekilasi elilodwa subtype - Golovohordovye. It yakhiwa inqwaba imisipha transverse izingqimba lizungezwe zezinzwa izicubu emgodleni. Lezi zingqimba ngabanye zihlukaniswa izimbobo emazinyweni, kodwa nabo eduze nge amaqhubu iDemo.

Ihlelo lokukhambisa iingazi

Kukholakala ukuthi isimiso sokujikeleza kwegazi lesilwane ivaliwe. Ngempela, akukho igazi izikhala, kodwa akukho capillary yangempela (thinnest izitsha ngodonga nge monolayer) kwegazi encane imithambo lwako isikhala intercellular (bona luhambisane ezisebenza capillary), futhi ngenxa yalokho eqoqwe emithanjeni emincane.

uhlelo zokuzala

Zaphansi Amphioxus uhlelo imelelwa uchungechunge gonads abhanqiwe (gonadal). Basuke etholakala ezindongeni ngalo ingaphakathi atrial. Bescherepnyh (lancelet kuhlanganise) dioecious. I gonads owesilisa nowesifazane yokuzenzisa efanayo, ezingafani kuphela ezidlula gametes (oocyte emikhulu). amaseli Mature zokuzala ngokusebenzisa igebe gonads odongeni iwela ingaphakathi atrial, lapho amanzi agelezayo kukhishelwa ngaphandle ngokusebenzisa atriopor. Ukuthuthukiswa kwenzeka abezindaba aqueous futhi lubonakala ngalolo kukhona esigabeni elalikudle lapho liseyisibungu.

Isakhiwo izibungu

Isakhiwo izibungu ngendlela eyinqaba kakhulu: kusaqalwa it libhekene ilungiselelo azilingani emlonyeni (ngakwesokunxele), kanye izimbotshana gill (ngakwesokudla), inani okuyinto encane ekuqaleni. kamuva omunye kuphela umugqa gill izimbotshana lithuthela esiswini, bese kuze kufike ohlangothini lwesobunxele, kanti umlomo is abangenamakhaya phansi. Isibalo gill ukuvuleka kukhuphuke ngo Slots Breakout eyengeziwe futhi obumba ngodonga longitudinal e akhona vele. Larva ngenkuthalo ihamba ngosizo cilia ukumboza umzimba, futhi kamuva ukugoba lateral komzimba, njenge amafomu omdala. Yena bathambekele yokudla asebenzayo izilwane ezincane planktonic. kwakhiwa uphondo Perioral nge tentacles kuphela ekupheleni ukuthuthukiswa elalikudle lapho liseyisibungu, isibungu, sengathi umzimba esekhulile, ushintsho ekuphileni phansi.

ingaphakathi atrial

Amphioxus - isilwane kokuba ingaphakathi atrial. Ngo ukuvulwa imbobo yakhe futhi gill izimbotshana metanefriliev. Lapha kufika amaqanda sesivuthiwe futhi isidoda. Konke lokhu kukhomba ukuthi uxhumano ingaphakathi atrial nge imvelo bangaphandle. Anatomically, lobu buhlobo imelelwa umgodi, okuthiwa atrioporom nokuvulwa phandle ohlangothini ventral wengxenye ezingemuva umzimba phambi ingquza. I esicace isixhumanisi atriralnoy ingaphakathi nge imvelo ebonakaliswa ubunjalo lasungulwa.

Larva Amphioxus umzimba ohlangothini izindonga ukuvuleka gill akhiwa longitudinal emphethweni metaplevralnye. Kancane kancane ukwandisa ohlangothini ezilingene phansi, bese tho ndawonye. Isikhala phakathi emphethweni futhi imele ingaphakathi atrial. Ngamanye amazwi, ngalo ingaphakathi atrial, esesikhundleni lancelet - kuyingxenye imvelo bangaphandle ethumba metaplevralnymi emphethweni. Ihlanganisa ingxenye uqhoqhoqho emathunjini, ingxenye enkulu ebusweni gonads, bangazihluphi isikhala olunzulu kakhulu displacing wonke, okuyinto kugcinwa kuphela ngesimo yebhangqa izimbotshana kanye emaphethelweni engenhla pharynx, kanye endostyle metaplevralnyh emphethweni.

Ukubaluleka begazi ingaphakathi atrial ngenxa ubunjalo Amphioxus isithombe uhlala. Lapho kungcwatshwa e esidayisa amanzi wesisekelo izimbotshana gill nzima, izinhlayiya inhlabathi Ungafaka izimbobo gill futhi clog kubo. Kumiswa ingaphakathi atrial, ukuvuleka kabani izindonga gill ehlukanisiwe nabo emhlabathini, kususa lesi sithiyo. Amanzi, ngezikhwepha ivela atriopora, kuqeda inhlabathi kule ndawo, ukuqinisekisa yokuphefumula mahhala futhi kukhuthaza imikhiqizo umzimba. Njengoba sekushiwo, e Amphioxus izibungu, okuholela izinhlanzi, ingaphakathi atrial khona. Ayikho-ke, futhi izinhlobo eziningana Amphioxididae umndeni ka izinhlanzi ehola nobudala.

Lawa izici eziyinhloko Amphioxus - omunye abameleli chordates.