Ectoderm - wannan m iri Layer

A ectoderm ne wani ɓangare na wani dabba kwayar kwayoyin. Kawai wasu da wannan tsarin ne kiyaye kawai a lokacin da amfrayo ci gaba, yayin da wasu - na rayuwa. Mene ne ectoderm?

Nau'in na kumshe yadudduka

A lokacin yanayin halitta na juya na kwan da ya hadu raba akai-akai, don samar da dama yadudduka na Kwayoyin kan lokaci. A lokacin da suka bambance ne da samuwar dama yadudduka na jiki, wanda daga baya za su samar daga kyallen takarda, gabobin da kuma tsarin. Ectoderm - wani yanki na cikin matsanancin germinal. A lokacin da ci gaban da zygote shi ne kafa wata farko m Layer na sel. A ciki leaf amfrayo kira da indodem. Daga baya shi ci gaba daga na numfashi da kuma narkewa kamar tsarin. Daga tsakiyar jam Layer - mesodam - kafa jikin da ze su ɗaure tare da dukan jiki. Shi ne tsokoki da jijiyoyin, ciki kwarangwal, haihuwa, Sistem da excretory tsarin.

Kalam na ectoderm

Ectoderm - a nucleation Layer, kafa na sel, wanda yake rufe da gabobin da juyayi tsarin. Its samuwar auku a gastrula mataki. A juyayi tsarin na vertabrate halin da wani babban matakin ci gaba. Ya kunshi kwakwalwa da kuma laka, kazalika da mutum zaruruwa cewa mika daga gare su, to duk Tsarin na jiki. Sense Gabobi da kuma haska tsarin da ake ma samu daga ectoderm. Kamar yadda tayi tasowa daga wani yanki na cikin matsanancin Layer na Kwayoyin, shi Forms wani shãmaki. Na farko farkon da epithelial nama da fata da kuma narkewa kamar tsarin.

ectoderm na hydra

A coelenterates dabbobi ectoderm - a jiki Layer cewa ta ci gaba cikin rayuwa. Yi la'akari da misalin tsarin ta ruwa tare hydra. Wannan biyu-Layer dabba wanda jiki ne kafa ta ecto- da indodem. A tsakãninsu akwai m farantin intercellular abu. ectoderm Kwayoyin suna bambanta a tsarin, da kuma ayyuka. A karo na farko a cikin juyin halitta daga irin wannan na musamman Tsarin bayyana kawai a cikin wakilan coelenterates.

A tsarin kunshi ectodermal fata-tsoka Kwayoyin, wanda suke iya yi mu'ãmalar. Godiya a gare su, da hydra ne motsi kamar an Acrobat, juya zuwa ga tafin a kan tentacles. Lokacin da fallasa su jijiya Kwayoyin, wanda ake kuma shirya a cikin matsanancin Layer na jiki, da dabba da aka matsa. Wannan shi ne wata alama ce ta reflex aiki. A matsanancin Layer ne ma zubar tsaka-tsaki da Kwayoyin cewa za a iya canza kama zuwa wani iri daban. Yana ma'anar da babban matakin dawo da ruwa tare hydra. Yana iya gaba daya mayar da jikinka, ko da daga mushy jihar.

Mene ne harbin Kwayoyin

Ectoderm - shi ne mai matsanancin Layer abin da hidima a matsayin abin dogara wajen na kariya da farauta. Wannan aiki da aka yi harbin Kwayoyin. Sun kunshi wani kwantena da wani Twisted ciki thread. Lokacin da aka azabtar ya wuce wurin, ta zo da m gashi. A sakamakon haka, harbin thread unwinds kuma yi tsananin bugãwa da cizon cikin jikinta. Tare da shi an gabatar da guba abubuwa. Gurgunta azabtar amfani feelers ne a cikin hanji lumen, inda shi ne narkewa. Mutane da yawa jinsunan jellyfish ne m da mutane. Aiki da harbin Kwayoyin sa mai tsanani konewa, rushewa daga cikin zuciya da kuma numfashi tsarin, da kuma wani lokacin har iyakar kuma mutuwar.

Saboda haka, da ectoderm ne m jam yadudduka, daga abin da milling aiwatar a vertabrate dimbin yawa jiki inuwõyi da kuma gabobin da juyayi tsarin. A coelenterates ectoderm Forms yawan qware Kwayoyin: fata, tsoka, tsaka-tsaki, jijiya da kuma harbin.