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== Struktura ==
=== Terminologija ===
The unusual microstructure of muscle cells has led [[cell biology|cell biologists]] to create specialized terminology. However, each term specific to muscle cells has a counterpart that is used in the terminology applied to other types of cells:
Neobična mikrostruktura mišićnih ćelija navela je [[Цитологија|citologe]] da stvore specijalizovanu terminologiju. Međutim, svaki izraz specifičan za mišićne ćelije ima protivrednost koja se koristi u terminologiji koja se primenjuje na druge vrste ćelija:
{| class="wikitable"
! Mišićna ćelija''' !! Druge ćelija organizma'''
|-
| [[sarcoplasm|sarkoplazma]] || [[cytoplasmcitoplazma]]
|-
| [[sarcoplasmic reticulum|sarkoplazmatični retikulum]] || [[smoothЕндоплазматични ретикулум|glatki endoplasmicendoplazmatični reticulumretikulum]] (SER)
|-
| sarcosomesarkozom || [[mitochondrionmitohondrija]]
|-
| [[sarcolemma|sarkolema]] || [[cellćelijska membranemembrana]]
|}
The [[sarcoplasm|Sarkoplazma]] is theje [[cytoplasmcitoplazma]] ofmišićnog a muscle fibervlakna. MostVećina ofsarkoplazme theje sarcoplasm is filled withispunjena [[myofibrilmiofibril]]sima, whichkoji aresu longduge proteinproteinske cordsniti composedsastavljene ofod myofilamentsmiofilamenata. TheSarkoplazma sarcoplasm isse alsotakođe composedsastoji ofod [[glycogenglikogen]]a, apolisaharida polysaccharideod ofglukoznih glucose monomersmonomera, whichkoji providesćeliji energydaje toenergiju thepri cellintenzivnom with heightened exercisevežbanju, andi [[myoglobinmioglobin]]a, thecrvenog redpigmenta pigmentkoji thatskladišti storeskiseonik oxygendok untilnije neededpotreban forza muscularmišićnu activityaktivnost.<ref name=saladin>{{cite book|last1=Saladin|first1=K|title=Anatomy & Physiology: The Unity of Form and Function|date=2012|publisher=McGraw-Hill|location=New York|isbn=978-0-07-337825-1|pages=403–405|edition=6th}}</ref>
There are three types of myofilaments:<ref name=saladin />
Postoje tri vrste miofilamenata:<ref name=saladin />
*Thick filaments, composed of protein molecules called [[myosin#myosin II|myosin]]. In striations of muscle bands, these are the dark filaments that make up the A band.
* Debeli filamenti, sastavljeni od molekula proteina zvanog [[miozin]]. U strijacijama mišićnih traka, to su tamne niti koje sačinjavaju A-bend.
*Thin filaments are composed of protein molecules called [[actin]]. In striations of muscle bands, these are the light filaments that make up the I band.
* Tanki filamenti su sastavljeni od molekula proteina zvanog [[aktin]]. U strijacijama mišićnih traka, to su lagana vlakna koja čine pojas I.
*Elastic filaments are composed of [[titin]], a large springy protein; these filaments anchor the thick filaments to the Z disc.
* Elastični filamenti su sačinjeni od [[titin]]a, velikog opružnog proteina; ove niti se učvršćuju debelim nitima na Z disku.
Ovi miofilamenti zajedno rade na stvaranju kontrakcije mišića.
Together, these myofilaments work to produce a muscle contraction.
The [[sarcoplasmic reticulum|Sarkoplazmatični retikulum]], aspecijalizovani specialized type oftip [[endoplasmicЕндоплазматични reticulum#smooth endoplasmic reticulumретикулум|smoothglatkog endoplasmicendoplazmatičnog reticulumretikuluma]], formsformira amrežu networkoko aroundsvakog eachmiofibrila myofibrilmišićnog of the muscle fibervlakna. ThisMreža networkje issastavljena composedod ofgrupa groupingsdva ofdilatatora, twonazvana dilatedterminalni end-sacs called terminal cisternaesudovi, andi ajedne single transversepoprečne tubule, orili [[T-tubula|T tubule]], whichkoji boresprolaze throughkroz thećeliju celli and emerge onizlaze thena otherdrugu sidestranu; togetherove thesetri threekomponente componentszajedno formčine thetrijade triadskoje thatpostoje existunutar withinmreže thesarkoplazmatskog network of the sarcoplasmic reticulumretikuluma, inu whichkojima eachsvaka T tubulecev hasima twopo terminaldva cisternaeterminalna onsuda eachsa sidesvake of itstrane. TheSarkoplazmatski sarcoplasmic reticulumretikulum servessluži askao reservoirrezervoar forza calciumjone ionskalcijuma, sopa whenkada anse actionakcioni potentialpotencijal spreadsširi over thepreko T tubuletubula, iton signalssignalizira thesarkoplazmatskom sarcoplasmicretikulumu reticulumda tooslobadi releasejone calciumkalcijuma ionsiz fromzapornih themembranskih gatedkanala membranekako channelsbi tose stimulatestimulisala a musclemišićna contractionkontrakcija.<ref name=saladin /><ref>{{cite journal |last1=Sugi|first1=Haruo |last2=Abe|first2=T |last3=Kobayashi|first3=T |last4=Chaen|first4=S |last5=Ohnuki|first5=Y |last6=Saeki|first6=Y |last7=Sugiura|first7=S |last8=Guerrero-Hernandez|first8=Agustin|title=Enhancement of force generated by individual myosin heads in skinned rabbit psoas muscle fibers at low ionic strength|journal=PLoS ONE |date=2013|volume=8 |issue=5|pages=e63658 |doi=10.1371/journal.pone.0063658 |pmid=23691080|pmc=3655179|bibcode=2013PLoSO...863658S}}</ref>
The [[sarcolemmaSarkolema]] is theje [[cellćelijska membranemembrana]] of a [[Striated muscle tissue|striatedprugastih musclemišićnih fibervlakana]] andkoja receivesprima andi conductsprovodi stimulipodražaje. AtNa thekraju endsvakog ofmišićnog each muscle fibervlakna, thespoljni outer layer ofsloj thesarkoleme sarcolemmase combineskombinuje withsa tendontetivskim fibersvlaknima.<ref name=Bentzinger2012>{{cite journal |last1=Bentzinger|first1=CF |last2=Wang|first2=YX|last3=Rudnicki |first3=MA|title=Building muscle: molecular regulation of myogenesis.|journal=Cold Spring Harbor Perspectives in Biology|date=1 February 2012 |volume=4|issue=2 |doi=10.1101/cshperspect.a008342|pmid=22300977|pages=a008342|pmc=3281568}}</ref> WithinUnutar themišićnog muscle fibervlakna pressedpritisnutog againstuz thesarkolemmu sarcolemmanalaze arese multiplevišestruko flattenedspljoštena [[cell nucleus|nucleijezgra]]; thisovo multinuclearmultinuklearno conditionstanje resultsrezultat fromje multiplevišestrukih myoblastsmioblasta fusingkoji tosu producespajeni eachpri muscleforomiranju fibersvakog mišićnog vlakna, wherepri eachčemu myoblastsvaki contributesmioblast onedoprinosi nucleusjednim jezgrom.<ref name=saladin />
=== Unutrašnja struktura ===
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