Question

Although all the anatomical parts of muscle work together to give it it's characteristics, which of the following proteins listed below would be most associated with the characteristics of excitability?A)-actin of thin filamentsB)-elastic (titin) filamentsC)-acetylcholine receptors in the motor end plateD)-the Na+-K+ pump

Answer 1

C) Acetylcholine receptors in the motor end plate

Step-by-step explanation:

Excitability is the ability of the muscle fiber to produce an electric signal in response to a stimulus. The motor end plate is the region of sarcolemma present opposite to the synaptic end bulbs. It is a muscular region with millions of integral membrane proteins serving as acetylcholine receptors.

The acetylcholine receptors are ligand-gated ion channels and acetylcholine serves as the ligand. Each of the ion channels of acetylcholine receptors is opened by binding of two molecules of acetylcholine. The opening of these ion channels allows Na+ to move across the membrane. The inflow of Na+ makes the inside of the muscle fibers more positive and triggers the firing of the action potential.