MUSCLE
SKELETAL MUSCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of these options best summarizes the SECOND phase of a muscle contraction?
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A stimulus from the neuron reaches the muscle fiber and stimulates an action potential in the muscle.
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The action potential travels along the sarcolemma and penetrates into the muscle fiber. Calcium is released by the SR and travels to the sarcomere.
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The cross bridge cycle occurs after calcium is released by the SR. During this cycle, the actin myofilaments are pulled towards the M line by the myosin myofilaments.
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None of the above
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Explanation:
Detailed explanation-1: -The process of muscular contraction occurs over a number of key steps, including: Depolarisation and calcium ion release. Actin and myosin cross-bridge formation.
Detailed explanation-2: -The energy is derived from adenosine triphosphate (ATP) present in muscles. Muscles tend to contain only limited quantities of ATP. When depleted, ATP needs to be resynthesized from other sources, namely creatine phosphate (CP) and muscle glycogen.
There is 1 question to complete.