PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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When the nerve and muscle are at rest
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their membranes are positive on the outside, negative on the inside
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their membranes are negative on the inside, positive on the outside
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myosin heads are in mid power stroke
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acetylcholine floods the synapse
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Explanation:
Detailed explanation-1: -A neuron at rest is negatively charged: the inside of a cell is approximately 70 millivolts more negative than the outside (−70 mV, note that this number varies by neuron type and by species).
Detailed explanation-2: -A neuron is at rest when it is not sending an an electrical signal. During this time, the inside of the neuron is negative relative to the outside.
Detailed explanation-3: -The relative excess of positive charges outside and negative charges inside the membrane of a nerve cell at rest is maintained because the lipid bilayer acts as a barrier to the diffusion of ions, and give rise to an electrical potential difference, which ranges from about 60 to 70 mV.
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