MUSCLE
SKELETAL MUSCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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ATP
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Power Stroke
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Cross Bridge
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none of the above
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Detailed explanation-1: -After the ATP hydrolysis takes place, the myosin head acquires a changed (cocked) position that facilitates the binding to the actin filament. The energy of the ATP hydrolysis is used for the bending of the actin-bound myosin (i.e., the bending of its S1 region). The bending is also called a power stroke.
Detailed explanation-2: -The power stroke requires the hydrolysis of ATP, which breaks a high-energy phosphate bond to release energy. Actin (red) interacts with myosin, shown in globular form (pink) and a filament form (black line).
Detailed explanation-3: -Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past each other, which is called the sliding filament model of muscle contraction. ATP provides the energy for cross-bridge formation and filament sliding.