Twitch Summation

Multiple Choice

Twitch summation

A) is a means by which gradation of muscle contraction may be accomplished
B) results from the additional release of Ca²⁺ within the cytosol of muscle fibers
C) results from increasing the frequency at which motor units are firing within a muscle
D) is a means by which gradation of muscle contraction may be accomplished and results from increasing the frequency at which motor units are firing within a muscle
E) all of these