PHYSIOLOGY
MUSCLE STRUCTURE FUNCTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the myosin head goes into the cocked or ready position
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myosin head pulls on the actin and the sarcomere shortens
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The myosin head enters the high energy state and only binds to the actin filament
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the myosin head enters the low energy state
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Detailed explanation-1: -After the power stroke, ADP is released; however, the cross-bridge formed is still in place, and actin and myosin are bound together. ATP can then attach to myosin, which allows the cross-bridge cycle to start again and further muscle contraction can occur (Figure 6.8).
Detailed explanation-2: -At the end of the power stroke, the myosin is in a low-energy position. After the power stroke, ADP is released, but the cross-bridge formed is still in place. ATP then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.
Detailed explanation-3: -(c) During the power stroke, the phosphate generated in the previous contraction cycle is released. This results in the myosin head pivoting toward the center of the sarcomere, after which the attached ADP and phosphate group are released.