1. Contraction of Skeletal Muscle Sliding filament theory of contraction (Excitation-Contraction Coupling)

2. Functional Anatomy of Skeletal Muscle

8. Arrival of nerve impulse (action potential) Influx of Ca 2+ into the pre-synaptic membrane Attraction of synaptic vesicles Fusion of vesicular & pre-synaptic membranes Release of neurotransmitter (Ach) into the synaptic cleft Binding of Ach with its nicotinic receptor on post-synaptic membrane Influx of Na 1+ into the post-synaptic membraneFiring of action potential on post-synaptic membrane (sarcolemma)

9. Propagation of action potential along sarcolemma and deep via T-tubules Release of Ca 2+ from sarcoplasmic reticulum to be near the myofilaments

10. What happens at the sarcomere level?

11. full full contraction Sarcomere shortens toward

12. full full contraction Sarcomere shortens toward

13. full full contraction Sarcomere shortens toward

14. full full contraction Sarcomere shortens toward

15. Cleavage of ATP into ADP and P i Ca 2+ binds troponin C

16. Detachment of P i Actin-myosin cross-bridge

17. Tilting of myosin heads and sliding of actin along myosin

18. Relaxation Arrival of new ATP

19. The cycle is repeated

20. Detachment of P i

21. Sliding Sliding

22. Relaxation

23. The cycle is repeated

24. Until full Until full contraction The cycle is repeated

25. Until full Until full contraction The cycle is repeated

26. Until full Until full contraction The cycle is repeated

27. Accept my Best wishes