The long plateau phase of the cardiac muscle action potential is due to
a. increased membrane permeability to sodium ions.
b. calcium channels remaining open.
c. movement of fewer sodium ions across the cell membrane.
d. a decrease in the amount of calcium diffusing across the membrane. e. increased membrane permeability to potassium ion.

Option (a) is Right Answer

Explanation:

    (a) Increased membrane permeability to sodium ions

A resting (non-flagging) neuron has a voltage over its layer called the resting membrane potential, or basically the resting potential The resting potential is dictated by the focus angles of particles over the layer and by membrane permeability to each type of particle  This stage is called the "plateau" stage because of the membrane potential outstanding practically consistent, as the membrane gradually starts to repolarizeIt is because of the close to adjust of charge moving into and out of the cell