What is the best description of a tetanic contraction in a skeletal muscle cell?
A. A single action potential in the motor neuron causes a sustained contraction.
B. Multiple action potentials in the motor neuron cause a sustained contraction.
C. The action potential in the muscle cell is prolonged to last as long as the contraction.
D. Repeated action potentials from the motor neuron summate into a sustained depolarization of the motor end plate, causing a sustained contraction.
E. A very large amplitude action potential in the motor neuron causes a very strong contraction in the skeletal muscle cell.
B
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