Uhlelo lwe-peripheral nervous: zithini izingxenye zalo nemisebenzi?

Ubuchopho benziwa izingxenye nezindawo eziningi, kufaka phakathi i- uhlelo lwezinzwa, echazwa njengezakhiwo nezitho ezakhiwa izicubu zemizwa nezinhloso zazo ukuthola nokwenziwa kwamasiginali atholwe izitho ezahlukahlukene, ukuze kunikezwe impendulo efanelekile kuzinguquko ezingalethwa imvelo lapho kuhlala khona izilwane izilwane (abantu abaphakathi kwezingxabano, ama-arthropods, ama-mollusks, ama-flatworms nama-cnidarians).

Isistimu yezinzwa yakhiwe isistimu yezinzwa emaphakathi kanye ne-peripheral nervous system; esikhulume ngayo ngendlela ejwayelekile endatshaneni edlule (ungafinyelela ngokuchofoza lapha). Kodwa-ke, kulokhu sizogxila kakhulu emaphepheni, lapho sizothinta khona izihloko ezifana nemisebenzi yayo, izingxenye zayo nemidwebo yayo.

Luthini uhlelo lwe-peripheral nervous?

Yaziwa nangokuthi yi-SNP yayo (isifinyezo segama elifanayo), ibhekisa emithanjeni nasezinhlakeni, okuyizakhiwo ezingaphandle kobuchopho kanye uhlelo lwangaphakathi lwezinzwa (CNS); kodwa lokho nakho, kuvumela ukuxhumana phakathi kwe-CNS namalungu noma izitho zomzimba. Ngaphezu kwalokho, kubonakala (noma kwehlukile ohlelweni lwezinzwa oluphakathi) ngokungabi nokuvikelwa kubuthi noma ukulimala okubangelwa ukunyakaza.

Ngamanye amagama, uhlelo lwe-peripheral nervous luphethe Ukudidiyela nokulawula izitho itholakale ngaphakathi emzimbeni. Kulomsebenzi isebenzisa ifayili le- ama-axon, ukuqhubeka kwe-neuron ehlose ukuthumela imizwa yezinzwa kwamanye amaseli.

Ngaphezu kwalokho, ku-PNS ukuvuselelwa kwezilonda kungenzeka futhi ukuthuthukiswa kwama-axon kuyathuthukiswa ngenxa yamaseli weSchwann. Lokhu kungenxa yokuthi lezi (ezaziwa nangokuthi i- ama-neurolemocytes), angamaseli we-glial akhona kulolu hlelo ukuze ama-neurons akwazi ukusebenza kahle.

Ziyini izingxenye zayo?

I-SNP yakhiwe uhlelo lwe-somatic ne-autonomic system; yize lokhu kokugcina kuvame ukudideka ngokuthi "ukuhlukaniswa iziqeshana" komngcele, kanti empeleni kuyisici sako kuphela.

Uhlelo lwezinzwa lweSomatic

Uhlelo lwe-somatic nervous luhlukaniswe izinhlobo ezimbili zemizwa, umgogodla kanye ne-cranial. Yize kuzona zozimbili lezi zikhathi umsebenzi wazo uwukuthi dlulisa noma uthole imininingwane yezinzwaKokubili kunokungafani kwabo, okumele sikunikeze imininingwane ukuze ukuqonde kahle.

• Ngakolunye uhlangothi, izinzwa zomgogodla zifeza lo msebenzi emaphethelweni nasesiqwini, ukuthumela noma ukuthola imininingwane yezinzwa kusetshenziswa umgogodla njengomgogodla. Endabeni "yokuthumela" imininingwane, inhloso ukukhombisa isimo nesimo semisipha, amalunga nemikhawulo; ngenkathi "ithola" imiyalo yemoto ngentambo ekhethekile, okungukuthi, ngenxa yabo kungenzeka ukwenza ukunyakaza.
• Enye into yimithambo ye-cranial, ephethe izindawo ezingaphezulu, okungukuthi, intamo nekhanda. Lokhu kuthumela imininingwane yezinzwa etholwe yilezi zingxenye esimisweni sezinzwa esiyinhloko; ngenkathi intamo nekhanda bathola imiyalo yezimoto nge-CNS.

Uhlelo lwezinzwa lwe-Autonomic

Njengoba igama layo likhombisa, inesibopho semisebenzi esingayilawuli (ukuphefumula, ukugaya, phakathi kwabanye) ngoba basebenza ngokuzimela ngenxa yemiyalo ethunyelwe yisistimu yezinzwa emaphakathi. Phakathi kwemisebenzi yayo, sithola ukulawula imisipha yenhliziyo nebushelelezi, i-viscera nezindlala; ezenziwa ngamagatsha parasympathetic nozwela.

• El uhlelo lwe-parasympathetic Iphethe ngokuyinhloko ukulungiselela umzimba wethu ezimweni ezithile, noma ngabe uyilungiselela ukugaya ukudla noma ngenxa yezinsongo zangaphandle, njengokubalekela isimo (umzimba uphendula kahle futhi ezimweni eziningi, kungenzeka ukugijima ngokushesha okukhulu ngenxa yokusetha uhlelo).
• Uzwela, ngokwengxenye yalo, lunenhloso yokusebenza komzimba okulungile; isibonelo, ukubuyisela ukushaya kwenhliziyo esimweni sayo esijwayelekile ngemuva kokukuguqula nganoma yisiphi isizathu.

Yini izinzwa ze-PNS?

Izinzwa zesistimu yezinzwa eziseduze zingahlukaniswa zibe yizinhlobo ezintathu: izinzwa ze-cranial, izinzwa zezitho ezingenhla nezinzwa zezitho ezingezansi.

• Kunezinzwa eziyishumi nambili ze-cranial, ezivela ebuchosheni noma eduze kwesiqu sobuchopho, yize zehluka ngokuya ngomsebenzi okufanele ugcwaliswe futhi zisatshalaliswa ezingxenyeni ezihlukene zomzimba, njengogebhezi, isifuba, intamo nesisu. Lezi izi izinzwa zezinzwa futhi zihlukaniswe imizwa olfactory, optic, oculomotor, trochlear, trigeminal, abducent, ebusweni, auditory, glossopharyngeal, vagus, accessory, kanye ne-hypoglossal.
• Izinzwa zezitho ezingenhla nezingezansi zibhekisa emithanjeni ekwazi ukudlulisa imizwa njengokushisa, amazinga obuhlungu, ukuma kwamaphethelo, phakathi kwabanye. Kunezimbhangqwana ezingama-31 zazo futhi zitholakala entanyeni, esifubeni, emuva, e-sacrum nase-coccyx.

Siyethemba ukuthi imininingwane ikuthande futhi ifundeka kalula, ngoba lezi zihloko kwesinye isikhathi zingaba nzima uma ungenalo ulwazi lwangaphambilini mayelana nokwakheka nokusebenza kwezinto ezakha ubuchopho noma umzimba.