Motor naúrar - abin da yake da shi?

Motor ko mota naúrar ne a rukuni na zaruruwa wanda ake innervated da wani motoneuron. The adadin zaruruwa na ga guda naúrar, za su iya bambanta dangane da aiki na tsokoki. The karami motsi da shi na samar, da karami da mota naúra da kuma kasa kokarin zama dole domin ta zumudi.

Motor raka'a: su rarrabuwa.

A cikin nazarin wannan topic ne wani muhimmin lokaci. Wadanne ma'auni da wanda wani motor naúrar za a iya halin. Physiology matsayin kimiyya, gano sharudda biyu:

• gudun raguwa a mayar da martani ga wani Holding sigina.
• gajiya gudun.

Haka kuma, a kan tushen da wadannan Manuniya, iri uku motor raka'a za a iya bambanta.

1. Sannu a hankali, ba tare da gajiya ba. Su motor neurons dauke da wani yawa na myoglobin, wanda yana da babban dangantaka for oxygen. Tsokoki da suke a mai yawa jinkirin motor neurons ake kira ja saboda su musamman launi. Suna da ake bukata domin kula da mutum hali da kuma ci gaba da shi a cikin balance.
2. Quick, tayoyin. Wadannan tsokoki iya yi a manyan yawan cuts a cikin wani gajeren lokaci. Zaruruwa su dauke da makamashi mai yawa abu daga wanda ta hanyar oxidative phosphorylation za a iya samu kwayoyin na ATP.
3. Fast, resistant gajiya. Wadannan zaruruwa dauke da 'yan mitochondria, kuma ATP kafa ta tsakiyan nonon mata na glucose kwayoyin. Wadannan tsokoki ake kira fari saboda sun rasa myoglobin.

A raka'a ta farko irin

A propulsion naúrar na farko da irin ko jinkirin neutomlyaemaya, na faruwa mafi sau da yawa a cikin ya fi girma tsokoki. Irin wannan motoneurons da low zumudi bakin kofa da sauri na jijiya turu. Jamhuriyar jijiya cell outgrowth a cikin m rabo ne branched da kananan fiber innervates kungiyar. A mita na jini zuwa ga jinkirin motor raka'a - daga shida zuwa goma hatsaisai da na biyu. Motoneuron iya tallafawa irin wannan kari a cikin 'yan dubun minti.

Ikon da gudun rage motor raka'a ta farko irin da rabi sau kasa da sauran iri motor raka'a. Dalilin wannan - low kudi na ATP da kuma jinkirin jimloli na alli ions a cikin matsanancin jikin tantanin ga dauri ga troponin.

A raka'a ta biyu irin

A propulsion naúrar na da irin wannan yana da babban mota-neurone tare da wani lokacin farin ciki da kuma dogon axons cewa innervate wani babban gungu na tsoka zaruruwa. Wadannan jijiya Kwayoyin suna da mafi dokin zumudi, da babban gudun jijiyar.

A iyakar ƙarfin lantarki na tsoka, jijiya bugun jini mita iya zama har zuwa hamsin seconds. Amma motoneuron ba zai iya kula da wani dogon lokacin da madugu gudu haka azumi gaji. A ƙarfi da kudi na raguwa a tsoka zaruruwa na biyu da irin fi baya daya, tun da adadin myofibrils cikinta more. A zaruruwa dauke da yawa enzymes cewa karya saukar glucose amma kasa mitochondrial gina jiki myoglobin da jini.

Raka'a na uku irin

A propulsion naúrar na uku irin su azumi, amma resistant gajiya da tsoka zaruruwa. A cewar ta halaye da shi dole ne ya dauki wani tsaka-tsaki darajar tsakanin farko da irin da na biyu motor raka'a. A tsoka zaruruwa na tsokoki karfi, da sauri da kuma m. Domin samar da makamashi da shi na iya amfani da biyu aerobic da anaerobic hanya.

A rabo daga azumi da kuma jinkirin zaruruwa ne genetically niyya da kuma na iya bambanta a daban-daban mutane. Wannan shi ne dalilin da ya sa wani abu ne mai kyau a nesa Gudun, wani sauƙi nasara da ɗari mita Gudu, da kuma wani more dace nauyi.

Reflex zuwa da tashin hankali da kuma mota neuron pool

Lokacin da mikewa kowane tsoka fiber rage na farko don amsa. Su neurons samar da jini har zuwa goma hatsaisai da na biyu. Idan tsoka don ci gaba da budewa, da generated bugun jini mita zai kara zuwa hamsin. Wannan zai kai ga a rage motor raka'a na uku irin, da kuma kara tsoka ƙarfi tenfold. Bayan kara mikewa gama motor zaruruwa na biyu da irin. Wannan zai ninka ikon tsokoki da baya a hudu ko sau biyar.

A propulsion naúrar na tsoka da aka sarrafawa da mota neurons. A sa na jijiya Kwayoyin cewa yin up wata tsoka, da ake kira motor neuron pool. A daya pool iya zama lokaci guda daga daban-daban neurons, ingantaccen da kuma gwada yawa nuni, motor raka'a. Saboda wannan, rabo na da tsoka zaruruwa kunshe a cikin jobs lokaci guda kuma zuwa mutuža cewa shi qara da tashin hankali da kuma gudun jijiyar.

"Ka'idar da darajar"

A propulsion naúrar na tsoka, dangane da irin, an rage kawai a lokacin da wani dokin load. Hanya zumudi stereotyped motor raka'a: na farko rage lafiya motor neurons, jijiyar suna nan a hankali samu zuwa manyan. Wannan juna a tsakiyar karni na ashirin da gan Edvud Henneman. Ya kira shi "da manufa na dabi'u."

Brown da kuma Bronk rabin karni baya aka buga da ayyukansu a kan nazarin manufa na aiki iri-iri na murdede raka'a. Sun yi shawarar cewa akwai hanyoyi biyu don sarrafa ƙanƙancewa na tsoka zaruruwa. A farko daga cikin wadannan - shi ne ya ƙara mita na jijiyar da sauran - tafiyar a cikin tsari kamar yadda zai yiwu adadin mota neurons.