'Epekema kālaimeaola: chord - o ka piko o ka holoholona kino

He aha hana i ka mano, ka honua toad, he python, he manu nunu la, Dolphin a me ke kanaka? Ma mua kilohi, ka mea i ai ma ko oko meaola mai kekahi i kekahi, o ka poe ma ka nānā aku, a me ka mea, i ka mea ai, a ma kahi e noho ai. Pehea la e hiki ai e wehewehe ana i ka hoʻohui o ka 'epekema kālaimeaola?

Ka chord - ke kino i hanaʻia i embryogenesis i loko o kēia mau kānaka a pau o ka Honua. Mai a ia originated? He aha e ka mana o ka chord a me ka holoholona ia me? Ma ka ninau ua manawa, e loaʻa mākou i nā pane i loko o kēia 'atikala. Nā examples aka ma lalo, kahaki i ke 'ano o ka chordates a me kā lākou mau alakaʻi o kūlana ma maoli me kona pono.

Ano o ka iho kino vertebrates

A pau i nā hiʻona o ka 'ole a me ka functioning hoʻomaopop' ana i ka 42 tausani laha 'o nā mea e ola ana i pili i ka chordal type, këia kālaimeaola. Ke chord - o ka papa kuhikuhiE anatomical ana hoʻohālike e hoohui mai ia mau meaola i loko o ka hookahi kahua hoʻonohonohoʻana pa alima. He he laholio kaula, a he o connective'aʻaʻa keena, i hoakaka kākoʻo ma ke kino. Ke notochord Ua aia ma ke kino a me ka pilikia ma ke ola i loko o kekahi laha ', i kapaʻia ka lalo chord. Ka mea, e ka poeikohoia o ka superclass jawless: lamprey a me ka hagfish. Ma cartilaginous iʻa, mano a me na kukuna, me ka iwi holoʻokoʻa ua haku o connective'aʻaʻa, a i ka like 'ole e like me ka chord. Ua, ma ka huli, ua waiho i loko o kēia mau meaola ola.

He aha kūpono i loko o ka muli o ka na iwi

He aha ka ke ano o ka chord? Kālaimeaola E hoomanao i kona helehelena ma Amphioxus, a laila nā holoholona nui aromorphosis. Ka mea, ua alakai ai i ka hooulu ana o ke kākoʻo'ōnaehana a me ka neʻeʻana i waho ma ka mua'āina holoholona. Ua 'ae' ia e kiʻi i ka i kā mākou pomaikai i loko o ka naʻi aupuni o ka aina, a me ke ku imua o, ka oi aku o ka hopena maikaʻi keiki o na koa o ka umekaumaha a me nā adverse? Aneie aʻe.

I ka nui holoholona pae, me ka olelo mai vertebrate cartilage auou caiaiai iho ili aku ai 'ole, a he o osseous oihana mua - vertebrae. Mau nā 'elele o ka hapanui papa o ka aina holoholona, e like me amphibians, mea kolo, a me nā manu mammals. No ka wai ola, me he iwi kuamoo, nā pūʻulu pokou ia: carps, Clupeiformes, Perciformes, a pela aku ...

Ma ka evolution o nā mea a pau o ka luna o nā pūʻulu o nā holoholona i noho ana i ka Hoʻohaku kulana i loko o ka? Aaoa o ka Honua. Keia ua kākoʻo 'ia e noiʻi i paʻa' epekema a me ka kālaimeaola. Ke chord - o ke kino, hiki i nā holoholona, e paʻi me na invertebrates i loko o ka paio no ka manawa.

First chordates

He nui zoologists,ʻepekema makemake e ike i ka holoholona, kona 'ole hiki ke noʻonoʻo me ka loulou ma waena o invertebrates a me vertebrates. Ma ka waena o ka XIX kenekulia Lūkini embryologist Kovalevsky ho'ākāka 'ia ma ka embryonic? Acaeoey unremarkable noho o ka Black Sea - Amphioxus mau.

Translucent kanaka a pau i ai i 8 knm, a e like me ka iʻa me ka poo chord hoopaa ma kona ola. Amphioxus hoao i ka malumalu palapala, i ke ola ana o ka i no i lōʻihi imi kālaimeaola. Chord - he 'ole, i ke ano o ka i keʻae i pono i ke ano o ka evolutionary ala. Hiʻona o ka embryonic 'ole (ke alo o ka germ papa ekolu) a me ontogenesis Amphioxus hoʻopaʻa i ka mea mahuʻi i nā kūpuna o nā chordates i meaola i i ole na iwi.

Bookmark ka iho iwi

Ho okumu ana o ka chord mai kekahi meaola mea e pili ana i ka ia, eia nae ka manawa wā mawaena ma i keia ia lŘlŘ hiki oko a. No ka laʻana, kanaka embryonic connectiveʻaha akaka i loko o ka au mua o embryonic? Acaeoey, a me kona uku pila mea māmā ma mua ia o ka iʻa a me nā vertebrates. Ke hoʻi paepae komo huila nuclei i hanaʻia ma lalo o ka neural Tube. Of iniiaiie intestinal hapa i kapaia o hordomezodermalnym appendage e hoʻomōhala ana i chord vertebrates.

Kālaimeaola a Medicine au mamuli izuchyut keʻano o ka hanaʻana 'ia i loko o ka pae o ka gastrulation e hōʻike' aʻe 'ana o fetal? Acaeoey, a e entail i emi ma viability, i ka ikea ana o abnormalities a me ka make ana o ka embryo. Ole maomeka lepe puke iho nā loko: ka neural Tube, notochord, liʻiliʻi - o ka noho pilikia loa, no laila, i ka maʻamau papa o ka hāpai keiki i loko o ka trimester mua mea nui loa no ke ola o ka unborn keiki.

Ke 'ano a me ka nui o keʻano chordwise

Nā 'elele o keia pae nui o ka meaola i no laila, pono hakuloli i kaʻokoʻa? Aneie aʻe i nohoia a pau o ka mea ma ka honua? Aneeo niches. Ma ka hydrosphere, e Birds piha ka home i oi aku mamua o 20 tausani. Fish? Ueo i i manaoia na chordates loa kahiko, i kaʻili a me ka hohonu o ka lithosphere me ka nui helu o ke ano o amphibians, mea kolo a me mammals, a me ka aina, a me ka ea i hoʻolilo 'noho ia e oi aku mamua o 8 tausani.. Byʻano o ka chord ia mea a me kanaka populations nona ka 'eleu fundamentally hoʻololi i ka maka o ko mākou Honua.