contraction of skeletal muscle sliding filament theory of contraction (excitation-contraction...
TRANSCRIPT
Contraction of Skeletal Muscle
Sliding filament theory of contraction
(Excitation-Contraction Coupling)
Functional Anatomy of
Skeletal Muscle
Arrival of nerve impulse (action potential)
Influx of Ca2+ into the pre-synaptic membraneAttraction of synaptic vesiclesFusion of vesicular & pre-synaptic membranesRelease of neurotransmitter (Ach) into the synaptic cleftBinding of Ach with its nicotinic receptor on post-synaptic membraneInflux of Na1+ into the post-synaptic membraneFiring of action potential on post-synaptic membrane (sarcolemma)
Propagation of action potential along Propagation of action potential along sarcolemma and deep via T-tubulessarcolemma and deep via T-tubules
Release of Ca2+ from sarcoplasmic reticulum to be near the myofilaments
What happens at the sarcomere level?
full full contractionSarcomere shortens towardSarcomere shortens toward
full full contractionSarcomere shortens towardSarcomere shortens toward
full full contractionSarcomere shortens towardSarcomere shortens toward
full full contractionSarcomere shortens towardSarcomere shortens toward
Cleavage of ATP into ADP and PCleavage of ATP into ADP and P ii
CaCa2+ 2+ binds troponin Cbinds troponin C
DetachmentDetachment of Pof Pii
Actin-myosin cross-bridgeActin-myosin cross-bridge
Tilting Tilting of myosin heads and of myosin heads and slidingsliding of actin along of actin along myosinmyosin
RelaxationRelaxation
Arrival of new Arrival of new ATPATP
The cycle is repeatedThe cycle is repeated
DetachmentDetachment of Pof Pii
SlidingSliding
SlidingSliding
RelaxationRelaxation
The cycle is repeatedThe cycle is repeated
Until full Until full contraction
The cycle is repeatedThe cycle is repeated
Until full Until full contraction
The cycle is repeatedThe cycle is repeated
Until full Until full contraction
The cycle is repeatedThe cycle is repeated
Accept Accept mymy
Best Best wisheswishes