MUSCLE NERVE CARTILAGE BONE
SKELETAL MUSCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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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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Detailed explanation-1: -A single contraction is called a twitch. A muscle twitch has a latent period, a contraction phase, and a relaxation phase.
Detailed explanation-2: -The contraction generated by a single action potential is called a muscle twitch. A single muscle twitch has three components. The latent period, or lag phase, the contraction phase, and the relaxation phase.
Detailed explanation-3: -Once the action potential reaches the end of the axon terminal, it causes the neurotransmitter acetylcholine (ACh) from synaptic vesicles in the axon terminal. The ACh molecules diffuse across the synaptic cleft and bind to the muscle fiber receptors, thereby initiating a muscle contraction.
Detailed explanation-4: -Three energy systems function to replenish ATP in muscle: (1) Phosphagen, (2) Glycolytic, and (3) Mitochondrial Respiration.