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***High '''glycolytic''' activity
 
***High '''glycolytic''' activity
 
***Function - exercise, bursts of activity
 
***Function - exercise, bursts of activity
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*Muscle activation is initiated by a nervous impulse crossing the Neuromuscular Junction
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**The neurotransmitter, Acetylcholine (Ach), binds receptors in the muscle fiber to open Na+ channels
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**This causes a wave of depolarization along the sarcoplasmic membrane, further opening voltage-gated Na+ channels, which propagates the signal along the sarcolemma
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**Depolarization of the sarcoplasmic reticulum causes Calcium to be released, which activates muscle contraction
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***Muscle contraction occurs when (thin) Actin filaments slide past (thick) Myosin filaments
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***Myosin heads bind Actin subunits, forming cross-bridges, hydrolyzing ATP and providing energy for contraction
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***Myosin heads undergo power stroke, displacing Actin and releasing ADP and Pi
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***Calcium regulates muscle contraction by binding troponin-C, which is attached to the thin filament
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***This causes inhibition of the steric block keeping Actin and Myosin from interacting
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**Increased Calcium causes a negative feedback inhibition of Ca release, and it is pumped back into the sarcoplasmic reticulum by the Ca/ATPase pump
    
==Tendon==
 
==Tendon==
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