PHYSIOLOGY
MUSCLE CONTRACTION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Subthreshold Stimulus
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Threshold Stimulus
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Maximal Stimulus
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Submaximal Stimuli
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Detailed explanation-1: -Definition: Sub-threshold (or subthreshold) refers to a stimulus that is too small in magnitude to produce an action potential in excitable cells . In general, a sub-threshold stimulus leads to the depolarization of the membrane, but the magnitude of the depolarization is not large enough to reach the threshold voltage.
Detailed explanation-2: -The minimum stimulus needed to achieve an action potential is called the threshold stimulus. The threshold stimulus causes the membrane potential to become less negative (because a stimulus, no matter how small, causes a few sodium channels to open and allows some positively-charged sodium ions to diffuse in).
Detailed explanation-3: -Answer and Explanation: A subthreshold stimulus is a stimulus that will cause a slight depolarization of a neuron’s membrane, but will not depolarize it to its threshold potential of-55 mV.