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: -Muscle contraction begins when the nervous system generates a signal. The signal, an impulse called an action potential, travels through a type of nerve cell called a motor neuron. The neuromuscular junction is the name of the place where the motor neuron reaches a muscle cell.
Detailed explanation-2: -Which of these options best summarizes the FIRST phase of a muscle contraction? A stimulus from the neuron reaches the muscle fiber and stimulates an action potential in the muscle.
Detailed explanation-3: -A twitch occurs when one muscle fiber contracts in response to a command (stimulus) by the nervous system. The time between the activation of a motor neuron until the muscle contraction occurs is called the lag phase (sometimes called the latent phase).
Detailed explanation-4: -Twitch. When stimulated by a single action potential a muscle contracts and then relaxes. The time between the stimulus and the initiation of contraction is termed the latent period, which is followed by the contraction period. At peak contraction the muscle relaxes and returns to its resting position.