When a muscle is unable to respond to stimuli temporarily, it is in which of the following periods?A) latent periodB) fatigue periodC) relaxation periodD) refractory period

D) refractory period

Explanation:

Electrical Muscle Stimulation is caused by the electrical impulses from brain that allows muscles to contract. A neurotransmitter junction between cells and neuron is presnet which cause action potential for muscle conraction.

The refractory period is the time when the cell is repolarizing. During refractory period cells re nable to repat its action and takes time to prepare the membrane for next stimulation. An action potential can't be transmitted until there is a potential across the membrane again.

Hence, refractory period is the time during which muscle is unable to respond to the stimuli.

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