CNS tsarin. jijiya fiber

Jijiya fiber outgrowth ne neuron, glial daina kai hare hare da aka rufi. Me ya sa yake dole? Abin da ya aikata? Mene ne tsarin? Wannan za ka koya daga labarin.

rarrabuwa

A zaruruwa na juyayi tsarin da daban-daban tsarin. A daidai da tsarin za su iya zama daya daga iri biyu. Saboda haka, ya zama ruwan dare unmyelinated da myelinated zaruruwa. A farko kunshi wani tsari cell, wanda aka located a tsakiyar tsarin. Shi ne ake kira mai axon (axons). Wannan tsari ne da kewaye da wani myelin daina kai hare hare. Ganin yanayin da aikin aza tsanani, da samuwar jijiya zaruruwa na wani ba irin. A tsarin da Tsarin dogara a kan sashi a cikin abin da suke located. Alal misali, a wani sashen somatic juyayi tsarin shirya myelinated jijiya zaruruwa, kuma vegetative - unmyelinated. Ya kamata a ce cewa samuwar wadannan da sauran Tsarin bin wani irin abin kwaikwaya.

Kamar yadda akwai wani bakin ciki jijiya fiber?

Ka yi la'akari da tsari a cikin mafi daki-daki. A mataki na samuwar Tsarin kamar unmyelinated axon delves cikin tufka kunshi lemmotsitov wanda tsitolemmy fara sag da kuma rufe kan aiwatar a kan manufa na hada guda biyu. Edge a cikin wannan kusa up na axon, da kuma kafa duplikatury da jikin tantanin, da ake kira "mezakson". Lemmotsity, located gaba kofa, an kafa tare da taimakon su tsitolemmy sauki lambobi. Unmyelinated zaruruwa saboda matalauta rufi iya wucewa a jijiya turu da mezaksona yankin da kuma a yankin na lamba tsakanin lemmotsitami. A sakamakon haka, shi ya wuce daga daya fiber zuwa wani.

Formation na lokacin farin ciki Tsarin

Jijiya fiber myelin ma thicker unmyelinated irin. Bisa ga tsari na kafa bawo ne m. Duk da haka, da kara gaban da neurons a somatic sashen, wanda ake dangantawa da ci gaban da dukan jiki, da inganta harkokin mikewa mezaksonov. Sa'an nan lemmotsity kunsa a kusa axons sau da yawa. A sakamakon haka, da concentric yadudduka an kafa irin, kuma da zuciyar an gusa daga cytoplasm zuwa karshe nada, wanda yake shi ne m daina kai hare hare na fiber (neurilemma). A ciki Layer kunshi mezaksona, entwined akai-akai kira myelin. A tsawon lokaci, da yawan jũya, kuma girma mezaksona hankali kara. Wannan shi ne saboda da nassi na aiwatar da myelination a lokacin axonal girma da kuma lemmotsitov. Kowane m bi da bi baya fadi. A mafi m ne daya cewa yana dauke da cytoplasm zuwa tsakiya lemmotsita. Bugu da ƙari, daban-daban myelin kauri da kuma bisa dukan tsawon na zare. A waɗannan wurare inda lemmotsity lamba tare da juna, da stratification vuya. The lamba shiga kawai cikin matsanancin yadudduka, wanda sun hada da cytoplasm da kuma tsakiya. Irin shafukan da aka kafa saboda rashin myelin thinning fiber kuma rundunar sunayen interceptions.

A ci gaba da Tsarin a tsakiya m tsarin

Myelination auku a cikin tsarin a sakamakon tafiyar matakai na oligodendrocytes kunsa axons. Myelin ne sia-akai da kuma a cikin hadin gwiwa tare da oxides samun duhu. Sauran gyara na membrane kuma ta interstices zama haske. Wadannan tube ake kira notches faruwa myelin. Su dace da kananan duwatsu a cikin cytoplasm lemmotsita. A axon a cytoplasm da mitochondria neurofibrils aka shirya longitudinally. Su mafiya yawan - kusa da sakonnin da, a karshen na'urorin zaruruwa. Tsitolemmy axon (axolemma) ya inganta jijiya turu. Yana bayyana ta kalaman na depolarization. A cikin akwati inda a matsayin axial Silinda neurite gabatar, shi ya ƙunshi basophilic granules abu.

tsarin

Myelinated jijiya zaruruwa kunshi:

1. Axon, wanda aka located a cibiyar.
2. Myelin daina kai hare hare. An rufe tare da Silinda axis.
3. Schwann harsashi.

A halin yanzu abun da ke ciki axial Silinda neurofibrils. A myelin daina kai hare hare da aka hada da wani jam'i na lipoid abubuwa kafa myelin. Wannan dangane yana da babban muhimmanci a tsakiya m tsarin. A musamman, shi kayyade gudun a da a aiwatar da zumudi a jijiya zaruruwa. A harsashi kafa fili axon rufe haka cewa gibba aka kafa, wanda aka kira nodes na Ranvier. A cikin yankin na lamba tare da Silinda axis of Schwann daina kai hare hare. fiber kashi - ta rata, wanda shi ne tsakanin biyu nodes na Ranvier. Yana iya a yi la'akari da zuciyar na Schwann daina kai hare hare. An located kamar a tsakiyar kashi. An kewaye da protoplasm na Schwann Kwayoyin tare da abun ciki na myelin a cikin madaukai. A tsakanin nodes na Ranvier myelin daina kai hare hare ba kama. Ya ƙunshi QFontDatabase notches Schmidt-Lanterman. Schwann jikin tantanin fara inganta daga ectoderm. Kasa su ne axon zaruruwa na gefe m tsarin, inda suka za a iya kira ta glial Kwayoyin. Jijiya zaruruwa a cikin tsakiyar tsarin bã tãre Schwann harsashi. A maimakon haka, akwai abubuwa na oligodendroglial. Unmyelinated fiber yana da kawai axons da Schwann daina kai hare hare a cikin abun da ke ciki.

aiki

Babban aikin yi da jijiya fiber - innervation. Wannan tsari shi ne na biyu iri: bugun jini da kuma bezimpulsnym. A farkon yanayin, da yaduwar na faruwa ne ta hanyar da electrolyte da neurotransmitter sunadaran. A innervation taka wata muhimmiyar rawa myelin, don haka gudun da tsari ne muhimmanci mafi girma a myelinated zaruruwa fiye da a unmyelinated. Tsari bezimpulsnogo irin auku axoplasm halin yanzu sunã gudãna a musamman axonal microtubules, wanda sun dauki trofogeny (abubuwa da suke da trophic effects).