Ginshikai na tsoka ƙanƙancewa. The ayyuka da kuma kaddarorin kwarangwal tsoka

Tsoka ƙanƙancewa - shi ne wani hadadden tsari ya kunshi wani yawan, saukarwa. Babban aka gyara a nan ne myosin, actin, troponin, tropomyosin da actomyosin, da alli ions da mahadi da cewa samar da tsoka makamashi. Ka yi la'akari da iri da kuma sunadaran da tsoka ƙanƙancewa. Bari mu yi nazarin, daga abin da suke yi da kuma matakan da ya kamata ga cyclical tsari.

tsokoki

Tsokoki ake hada cikin kungiyoyin, wanda da wannan inji na tsoka ƙanƙancewa. By guda alama sun kasu kashi 3 iri:

• striated tsokoki na jiki;
• striated tsokoki na atria da ventricles na zuciya;
• m tsoka gabobin, jini da kuma fata.

Striated tsokoki wani bangare ne na musculoskeletal tsarin, kasancewa wani ɓangare na shi, saboda ban da su, wannan ya hada da tendons, jijiyoyin, kasusuwa. Lokacin da aiwatar da tsarin ba da tsoka ƙanƙancewa, yi da wadannan ayyuka, da kuma ayyuka:

• jiki motsa.
• sassan jiki motsa zumunta da juna.
• jiki yana goyan bayan a sarari.
• zafi ne generated.
• bawo da aka kunna ta afferent ga receptive filayen tsoka.

Na m tsoka ne:

• motor na'ura na ciki gabobin, wanda ya hada da na Bronchial itace, da huhu da kuma narkewa kamar tube.
• da lymphatic da Sistem tsarin.
• tsarin urogenital gabobin.

physiological Properties

Kamar dukan vertabrate a cikin jikin mutum akwai uku mafi muhimmanci Properties na kwarangwal tsoka zaruruwa:

• contractility - rage da kuma canja irin ƙarfin lantarki idan m.
• watsin - motsi iya aiki a ko'ina cikin fiber.
• excitability - amsawa ga wani mai kara kuzari ta hanyar canza membrane m da ion permeability.

Tsokoki ne m, kuma za a fara samun koma baya ta jijiyar zuwa daga cibiyar. Amma a karkashin wucin gadi yanayi ta amfani da wutar lantarki ruri. A tsoka iya sa'an nan zama ya fusata kai tsaye (kai tsaye ruri) ko ta hanyar jijiya innervating tsoka (kai tsaye ba ruri).

iri cuts

Ginshikai na murdede ƙanƙancewa yana nufin tuba daga sinadaran makamashi cikin inji aiki. Wannan tsari za a iya auna gwaje da rana: ta maraƙi tsoka kaya low nauyi, sa'an nan hangula electroimpulses haske. A raguwa, a cikin abin da tsoka zama guntu, kira isotonic. rage faruwa a lokacin Yanar gizo ƙanƙancewa. Tendons ba da damar ci gaban da tsoka ƙarfi taqaitaccen. Wani auksotonichesky inji na tsoka ƙanƙancewa ya shafi yanayi na tsanani da danniya a lokacin da tsoka shortens kadan hanya, da kuma ikon su isa a kalla.

A tsarin da innervation na kwarangwal tsoka

A striated kwarangwal tsoka hada da wani iri-iri na zaruruwa a connective nama da kuma gyarawa zuwa tendons. A wasu tsoka zaruruwa aka shirya a layi daya da dogon axis, da kuma a wasu suna QFontDatabase ra'ayoyi, ana haɗe zuwa wani tsakiyar agara tyazhu kuma pinnate irin.

Babban siffa daga cikin fiber ne sarcoplasm taro na lafiya zaren - myofibrils. Su ne mai haske da kuma duhu yankunan alternating tare da juna, yayin da m striated zaruruwa ne ja ruwa - a giciye-sashe. Wannan results a giciye-Ha] a kusa da tsoka zaruruwa.

Sarcomere ne mai hadaddun, duhu kuma biyu haske woje, kuma shi delimited Z-dimbin yawa Lines. Sarcomeres - a contractile na'ura na tsoka. Sai dai itace cewa contractile tsoka fiber kunshi:

• contractile inji (myofibrils tsarin).
• trophic na'ura tare da mitochondria, Golgi hadaddun da kuma raunana endoplasmic reticulum .
• da membrane na'urar.
• reference na'ura;
• m na'ura.

Muscle fiber ne zuwa kashi 5 sassa da wa gininsu da kuma ayyuka, da kuma wani ɓangare daga cikin tsoka nama.

innervation

Wannan tsari a striated tsoka zaruruwa gane da jijiya zaruruwa, wato axons na mota neurons na laka da kuma kwakwalwa kara. Daya motoneuron innervate dama tsoka zaruruwa. Complex da motoneuron da innervated tsoka zaruruwa kira neuromotor (HME) ko wani motor naúrar (HU). Average yawan zaruruwa, wanda innervates a motoneuron, characterizes DE tsoka, kira na juna innervation yawa. A karshen shi ne mafi girma a cikin tsokoki, inda kananan ƙungiyoyi da kuma "bakin ciki" (idanu, yatsunsu, harshe). Its darajar ne kananan, a akasin haka, a cikin tsoka tare da "m" motsi (msl, jiki).

Innervation iya zama guda da mahara. A cikin farko idan aka gane m motor endings. Yawancin lokaci shi ne na hali na manyan motor neurons. Muscle zaruruwa (da ake kira a cikin wannan hali, ta jiki, ko azumi) da samar da PD (mataki iko) da shafi su.

Mahara innervation faruwa, misali, a cikin waje ido tsokoki. Wannan ba wani mataki m aka generated, tun da membrane ba electroexcitability sodium tashoshi. Suna rarraba a ko'ina cikin fiber depolarization na synaptic endings. Wannan shi ne zama dole domin kunna inji na tsoka ƙanƙancewa. A tsari a nan shi ne ba kamar yadda azumi kamar yadda a farkon harka. Saboda haka, shi ne ake kira jinkirin.

A tsarin da myofibrils

tsoka fiber bincike da aka fitar a yau a kan tushen da X-ray diffraction, electron bincike da madubin likita, da kuma histochemical hanyoyin.

Yana da aka lasafta cewa a kowane myofibril, da diamita daga abin da yake 1 micron, ya hada da kimanin 2,500 protofibrils, Ina nufin elongated polymerized kwayoyin sunadaran (actin da myosin). Actin protofibrils sau biyu thinner myosin. A sauran, wadannan tsokoki suna located haka cewa actin filament tips shiga cikin sarari tsakanin myosin protofibrils.

A kunkuntar tsiri na haske a cikin faifai A ne free daga actin filaments. A membrane Z da yake riƙe su tare.

A myosin filaments da mai gangara protrusions har zuwa 20 nm, a cikin shugabannin da ke game da 150 myosin kwayoyin. Su tashi biopolyarno, da kuma kowane shugaban myosinic haɗu da actin filament. Lokacin da akwai danniya a kan filaments na actin cibiyoyin myosin, actin filament ne kusa da tsakiyar sarcomere. A ƙarshen myosin filaments isa line Z. Sai suka dauki dukan sarcomere, kuma actin ne, daga gare su. A daidai wannan lokaci na fitar da tsawon an rage, da kuma a karshen shi vuya gaba ɗaya, tare da abin da line Z zama thicker.

Saboda haka, bisa ga ka'idar motsi yarns, saboda rage tsawon na tsoka zaruruwa. A ka'idar, da ake kira "kaya", da aka ɓullo da Huxley da Hanson a tsakiyar karni na ashirin da.

Hanyar tsoka fiber ƙanƙancewa

Babban ka'idar cewa babu filament (myosin da actin) suna taqaitaccen. Su tsawon zauna canzawa da tsoka tashin hankali. Amma daure na bakin ciki filaments, slipping, je tsakanin m filaments, rage-rage na digiri na zoba, don haka akwai wani raguwa.

A kwayoyin inji na murdede ƙanƙancewa ne kamar haka ta zamiya actin filaments. Myosin shugaban alaka protofibrils da actin. Tare da su gangara can ne zamiya, motsa actin filament zuwa tsakiyar sarcomere. Saboda da bipolar kungiyar na myosin kwayoyin a garesu na filaments, da yanayi na zamiya na actin filaments a daban-daban kwatance.

Lokacin da tsoka shakatawa myosin shugaban motsa daga actin filaments. Tare da wani sauki zamewa annashuwa tsoka tashin hankali kãfira da yawa kasa. Saboda haka, suna passively tsawo.

rage matakai

Ginshikai na murdede ƙanƙancewa za a iya taƙaice kasu kashi wadannan matakai:

1. Muscle fiber aka kara kuzari a lokacin da wani mataki m ake kawota daga mota neurons na synapses.
2. A mataki m aka generated a kan membrane na tsoka fiber, sa'an nan shimfidawa da myofibrils.
3. Fitaccen electromechanical biyu wakiltar wani hira na lantarki cikin inji da zamiya PD. Wannan dole ya shafi alli ions.

alli ions

Domin mafi fahimtar aiwatar da fiber kunnawa da alli ions ne dace a yi la'akari da tsarin da actin filament. Its tsawon shi ne game da 1 micron, kauri - daga 5 zuwa 7 nm. Wannan shi ne wani biyu daga Twisted zaren, wanda kama da actin monomer. Aƙalla kowane 40 nm nan ne siffar zobe troponin DNA, da kuma tsakanin sarƙoƙi - tropomiozinovye.

Lokacin da alli ions ne ba ya nan, watau myofibrils shakata dogon tropomiozinovye kwayoyin toshe abin da aka makala na actin, sarƙoƙi da myosin da gadoji. Amma lokacin da kunna alli ions tropomiozinovye kwayoyin nutse zurfi da kuma bude yankunan.

Sai myosin gadoji suna a haɗe zuwa actin filaments da ATP ta tsãge kuma tasowa tsoka ƙarfi. Wannan shi ne zai yiwu saboda da tasiri na alli troponin. A wannan kwayoyin da karshen ne maras kyau, sa'an nan turawa tropomyosin.

Lokacin da tsoka ne annashuwa, shi ne 1 gram rigar nauyi ya ƙunshi fiye da 1 mmol na alli. Alli salts ne ya zama ruwan dare da kuma musamman ajiya wurare. In ba haka ba, da tsokoki zai ko da yaushe ki.

alli ajiyar kamar haka. A bangarori daban-daban na diaphragm tsoka Kwayoyin a cikin fiber ne shambura ta hanyar da akwai wani dangane da yanayi wajen Kwayoyin. Yana da wani tsarin da mai gangara tubules. A tsarin ne perpendicular zuwa a tsaye iyakar abin da - vesicles (m) tankuna ana shirya a kusa da kusanci zuwa ga mai gangara diaphragms tsarin. Tare samu triad. Sai ya zama a vials adana alli.

Tun PD ne rarraba a cikin cell, kuma akwai wani electromechanical Tasrifu. Zumudi ratsa cikin fiber wuce a cikin wani a tsaye tsarin sake alli. Kamar wancan rage inji aka kwashe tsoka zaruruwa.

3 aiwatar da ATP

A cikin hulda da biyu strands a gaban alli ions wani babba rawa ga ATP. Lokacin da aiwatar da tsarin ba da tsoka ƙanƙancewa na kwarangwal tsokoki, da samar da makamashi na ATP da aka yi amfani da su:

• aiki na sodium da kuma potassium famfo wanda kula akai taro na ions.
• wadannan abubuwa a kan daban-daban tarnaƙi na membrane.
• zamiya filaments rage myofibrils.
• Ayuba alli famfo aiki shakata.

ATP ne jikin tantanin, da filaments na myosin da sarcoplasmic reticulum membranes. Enzymes karya saukar da zubar da myosin.

amfani na ATP

An sani cewa myosin shugabannin hulɗa tare da actin kuma ƙunshi abubuwa for ATP tsakiyan nonon. Last kunna actin da myosin a gaban magnesium ions. Saboda haka enzyme tsakiyan nonon faruwa a lokacin da a haɗe zuwa actin myosin kai. A mafi girma da giciye-gadoji, tsagawa gudun zai zama mafi girma.

ATP inji

Bayan kammala da motsi na da AFL kwayoyin samar da makamashi domin rabuwa da dauki da hannu a actin da myosin. Myosin shugaban rabu, ATP da aka cleaved zuwa Phosphate da ADP. A sabon karshen an haɗa ATP kwayoyin da sake zagayowar ya dawo. Irin wannan ne inji na tsoka ƙanƙancewa da shakatawa a matakin kwayoyin.

The aiki na giciye-gadoji zai šauki ne kawai muddin ATP hydrolysis faruwa. Idan ka toshe enzyme gadoji ba za a haɗe da sake.

Tare da farko na da mutuwa da kwayoyin matakin na ATP a cikin sel da dama da kuma gadoji kasance stably gyarawa zuwa actin filament. Saboda haka akwai mataki na rigor mortis.

ATP resynthesis

Resynthesis za a iya aiwatar a hanyoyi biyu.

By enzymatic canja wuri na phosphate kungiyar daga creatine phosphate zuwa ADP. Tun da hannun jari na creatine a cikin cell yafi ATP resynthesis aiwatar da sauri sosai. A lokaci guda, da hadawan abu da iskar shaka na pyruvic acid da kuma lactic acid resynthesis zai zama jinkirin.

ATP da kuma CP iya bace gaba daya idan resynthesis ne karye poisons. Sa'an nan da alli famfo tasha aiki, sakamakon tsoka ne mafita rage (watau zo contracture). Saboda haka, karya inji na murdede ƙanƙancewa.

Physiology tsari

A takaice, za mu lura cewa akan rage tsoka zaruruwa ne taqaitaccen a kowane na myofibrils sarcomeres. A filaments na myosin (m) da kuma actin (bakin ciki) da alaka iyakar a wani annashuwa jihar. Amma da suka fara zamiya motsi ga juna, idan aka aiwatar inji na tsoka ƙanƙancewa. Physiology (takaice) ya bayyana aiwatar a lokacin da ya rinjayi myosin da aka saki da makamashin da ake bukata don maida ATP zuwa ADP. Kamar wancan myosin aiki za a gane kawai a lokacin da wani isasshen abun ciki na alli ions tara a cikin sarcoplasmic reticulum.