Where does blood flow after it has returned from the pulmonary circuit?

Which layer of the serous pericardium is also considered the epicardium?

What structures help prevent back flow through the atrioventricular (AV) valves?

What valve lies between the left atrium and left ventricle?

Which structures are found within the atria? Choose all that apply.

What is the effect of Acetylcholine (Ach) on the cells of the SA node?

Relative to stroke volume (SV), sympathetic stimulation will ___.

The fetal heart begins to beat and pump blood around week ___.