Motor iyunithi - kuyini?

Motor noma motor Phiko iqembu imicu zazo innervated ngumuntu motoneuron. Inani imicu okuqondene iyunithi efanayo, ingase yehluke kuye ngesistimu umsebenzi imisipha. Le nhlangano yenkolo yokulwela ezincane ihlinzeka, ezincane motor unit and umzamo kancane kuyadingeka ukuze excitation yayo.

Motor amayunithi: ngezigaba zabo.

Ekuhloleni lesi sihloko osemqoka. Ingabe nenqubo ngawo iyiphi imoto iyunithi lungachazwa. Physiology njengoba isayensi, ikhomba zindlela ezimbili:

• ukunciphisa ijubane ephendula isignali eliyifa;
• isivinini ukukhathala.

Ngakho, ngesisekelo ngalezi zinkomba, ezintathu izinhlobo motor amayunithi ungabahlukanisa.

1. Kancane kancane, ningaphezi. motor yabo izinzwa aqukethe eningi myoglobin, esesikhundleni ziyezwana ephezulu umoya-mpilo. Izicubu e eziningi kancane Izinzwa abizwa ngokuthi abomvu ngenxa umbala othize. Balindeleke ukuba bakwazi ukugcina isimo womuntu futhi uyigcine ibhalansi.
2. Quick, amathayi. Lezi imisipha akwazi ukwenza inani elikhulu ukusikeka esikhathini esifushane. Ukotini Wekhethelo kubo aqukethe amandla amaningi impahla kuyiphi esebenzisa phosphorylation oxidative ingatholakala molecule ATP.
3. Fast, amelana ukukhathala. Le micu aqukethe mitochondria ambalwa, futhi ATP ezakhiwe cleavage glucose molecule. Lezi imisipha abizwa ngokuthi ezimhlophe ngoba bengafuni myoglobin.

Amayunithi Uhlobo lokuqala

I ngamandla iyunithi uhlobo lokuqala noma neutomlyaemaya kancane, kwenzeka kaningi imisipha emikhulu. motoneurons okunjalo abe ongaphakeme excitation embundwini futhi ijubane emsipheni ungacabanganga. Central ezinzwa cell yayifanekisela nomxhantela ukugcina yayo ngxenye branched futhi fibre encane innervates iqembu. Imvamisa esithweni oza kancane motor amayunithi - kusukela pulses ngomzuzwana eziyisithupha kuya kweziyishumi. Motoneuron engasekela isigqi zingakapheli emashumini ambalwa imizuzu.

Amandla nesivinini ekunciphiseni motor amayunithi yohlobo wokuqala nengxenye izikhathi esingaphansi nezinye izinhlobo motor amayunithi. Isizathu salokhu - Izinga eliphansi ATP kanye Imiphumela kancane kwe-calcium ion in the yangaphandle cell ulwelwesi ngoba sesibopho ukuthobisa troponin.

Amayunithi Uhlobo lwesibili

I ngamandla iyunithi lolu hlobo has a esikhulu motor-neurone nge axons uqweqwe eside ukuthi innervate kweqembu elikhulu kwemisipha zesivikelo sesifuba. La mangqamuzana ezinzwa babe embundwini eliphezulu kakhulu excitation futhi ijubane eliphezulu emsipheni amaza.

Ngezinye voltage esiphezulu kwemisipha, nerve ishayela imvamisa lingafika ku imizuzwana, anamanci mahlanu. Kodwa motoneuron akakwazi ulondoloza eside conduction Isivinini ngakho okusheshayo ukhathele. Amandla kanye izinga lokwehliswa imisipha Imicu yotshani Uhlobo lwesibili ephakeme kunaleyo yangaphambili, kusukela inani myofibrils therein ngaphezulu. Le micu aqukethe enzyme eziningi sokudiliza glucose kodwa amaprotheni myoglobin negazi izitsha kancane mitochondrial.

Amayunithi yohlobo wesithathu

I ngamandla iyunithi uhlobo lwesithathu kuyashesha, kodwa amelana ukukhathala kwezintambo zesivikelo sesifuba kwemisipha. Ngokusho izici zayo ke kumelwe athathe i value Lesisemkhatsini phakathi uhlobo lokuqala nelesibili motor amayunithi. Imisipha Imicu yotshani we imisipha, kuyashesha futhi ezinzima. Ukuze ukukhiqizwa energy ke angasebenzisa kokubili indlela aerobic kanye anaerobic.

Isilinganiso imicu kuyashesha futhi kancane bazimisele zofuzo futhi ziyahlukahluka kubantu abahlukene. Yingakho umuntu muhle at elide ukugijima, umuntu Onqobayo kalula engamakhulu amamitha Sprint, futhi othile weightlifting ehlelelwe more.

Reflex kuya ukungezwani futhi echibini motor neuron

Lapho esisuka silizwa imisipha ukubambezela kwabokuqala abamukela iqiniso. izinzwa zabo ukukhiqiza esithweni kuze kube pulses eziyishumi ngomzuzwana. Uma imisipha ukuqhubeka yokwelula, le elakhiwe ishayela imvamisa kuzokhulisa mahlanu. Lokhu kuzoholela ekuncipheni motor amayunithi yohlobo lwesithathu, futhi sandise amandla kwemisipha ngokuphindwe kayishumi. Lapho okwengeziwe esisuka ukuxhuma motor Imicu yotshani Uhlobo lwesibili. Lokhu ngizakwandisa imisipha amandla emuva izikhathi ezine noma ezinhlanu.

I ngamandla iyunithi imisipha ilawulwa Izinzwa. Isethi ezinzwa akha imisipha, ngokuthi motor neuron pool. Kokunye pool kungaba kanyekanye kusukela izinzwa ezahlukene, izibonisi qualitative ambalwa, motor amayunithi. Ngenxa yalokhu, izingxenye imisipha Imicu yotshani kufakwe imisebenzi kanyekanye futhi kangangoba kwandisa ukungezwani futhi ijubane emsipheni amaza.

"Isimiso yenani"

I ngamandla iyunithi imisipha, kuye ngokuthi hlobo yayo, kuyehla kuphela uma kombundu umthwalo ezithile. Inqubo excitation stereotyped motor amayunithi: lokuqala encishisiwe esihle Izinzwa, nerve amaza ke kancane kancane uthole elikhulu. Le ndlela phakathi kwekhulu lamashumi amabili wabona Edvud Henneman. Wasibiza ngokuthi "isimiso yamanani."

Brown kanye Bronk amahlanu ngaphambili eshicilelwe imisebenzi yabo ku ekutadisheni Umgomo we operation izinhlobo ezahlukene amayunithi kwemisipha. Bona baye basikisela ukuthi kunezindlela ezimbili ukulawula ukusikwa imisipha Imicu yotshani ukuphi. Eyokuqala yalezi - ukwenyusa imvamisa Izinzwa amaza kanye nezinye - ukuhlanganyela inqubo ngangokunokwenzeka inani Izinzwa.