7 terms

Role of ATP, Power Stroke, Muscle Contraction

Step 1
Relaxed Muscle, thin filament
Step 2
Sarcoplasmic reticulum releases Ca2+ into the sacroplasm.
Step 3
Myosin heads bind to actin
Step 4
Myosin heads swivel toward center of sarcomere (power stroke)
Step 5
ATP binds to the myosin head and detaches if from actin
Step 6
Hydrolysis of ATP transfers energy to myosin head and reorients it.
Step 7
Contractiion continues if ATP is available and Ca2+ level in the sarcoplasm is high.