Question

"The pacemaker potentials

*Na in K out* then *T-type Ca* channel open"
A) Sodium (Na+) influx and potassium (K+) efflux
B) Calcium (Ca2+) influx and sodium (Na+) efflux
C) Potassium (K+) influx and calcium (Ca2+) efflux
D) Chloride (Cl-) influx and sodium (Na+) efflux

Answer 1

In cardiac conductive cells, the pacemaker potential involves the influx of sodium ions (Na+) and the opening of T-type calcium channels, leading to depolarization.

Step-by-step explanation:

The action potential in cardiac conductive cells involves the movement of various ions, including sodium (Na+), potassium (K+), and calcium (Ca2+). At the beginning of the pacemaker potential, sodium ions (Na+) enter the cell, leading to depolarization. Then, T-type calcium channels open, allowing calcium ions (Ca2+) to enter the cell, further depolarizing it. This depolarization is necessary for the initiation of the action potential in cardiac conductive cells.