Question

Heart muscle cells spontaneously fire action potentials, with pacemaker properties but are subject to neural control by the sympathetic and parasympathetic nervous systems. Heart muscle cells are also electrically coupled. For each of the following, describe an experimental manipulation and the predicted result that would show it is true:

a. there is a chemical synapse between the vagus nerve and the heart muscle

changing the membrane potential

b.heart muscle cells are electrically coupled

c.the heart cells’ pacemaker properties are due to a leak of Na+ into the cell

Answer 1