PHYSIOLOGY
SYNAPTIC PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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myosin heads attach to actin
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myosin heads pivot pulling the actin filament toward the center
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cross-bridges detach from actin when a new ATP binds to myosin
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another cross-bridge forms
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Detailed explanation-1: -This process is known as myosin-actin cycling. As the myosin S1 segment binds and releases actin, it forms what are called cross bridges, which extend from the thick myosin filaments to the thin actin filaments. The contraction of myosin’s S1 region is called the power stroke (Figure 3).
Detailed explanation-2: -Key Points. ATP prepares myosin for binding with actin by moving it to a higher-energy state and a “cocked” position. Once the myosin forms a cross-bridge with actin, the Pi disassociates and the myosin undergoes the power stroke, reaching a lower energy state when the sarcomere shortens.
Detailed explanation-3: -Which of the following steps occurs right before the myosin head attaches to the actin during the sliding filaments? 1. The myosin head pivots.