Which of the following statements best summarizes excitation-contraction coupling?

a. a series of events in which an action potential triggers the release of chemical messengers.
b. a series of events in which calcium gradients are used to convey a signal to the muscle fiber to enact contraction.
c. a series of events in which an electrical stimulus is conveyed to a muscle fiber to enact contraction.
d. a series of events in which actin binds myosin to enact contraction.

C. A series of events in which an electrical stimulues is conveyed to a muscle fiber to enact contraction.

Explanation:

The excitation-contraction coupling is the physiological process that converts an electrical stimulus to a mechanical response; it is the action potential generated in the sarcolemma and the start of a muscle contraction. Electrical signals called action potentials travel through the neuron's axon, which branches through the muscle and connects individuals fibers at a neuromuscular junction.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.

voluntary muscles are controlled by the cerebellum.