PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Contraction
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Relaxation
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Either A or B
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None of the above
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Detailed explanation-1: -The contraction of myosin’s S1 region is called the power stroke (Figure 3). 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-2: -The powerstroke can be viewed as the result of three linked events: binding of the myosin head to actin, structural changes in the head leading to a strong actomyosin interaction, and the lever swing. These events lead to the release of ATP hydrolysis products, Pi (inorganic phosphate) and ADP.
Detailed explanation-3: -The power stroke is an engine operation Stroke in which hot expanding gases force the piston head away from the cylinder head. Piston force and subsequent motion are transferred through the connecting rod to apply torque to the crankshaft. The torque applied initiates crankshaft rotation.