Jones and Bartlett EMT Course Practice Test

The upper chambers of the heart are referred to as atria (singular: atrium). These two chambers play a crucial role in the cardiac cycle. Their primary function is to receive blood returning to the heart. The right atrium receives deoxygenated blood from the body through the superior and inferior vena cavae, while the left atrium receives oxygenated blood from the lungs via the pulmonary veins. This distinction is important for understanding how blood circulation works in the body.

The function and location of the atria are essential for the overall mechanics of the heart. They serve as the initial receiving chambers that fill with blood before it passes into the lower chambers of the heart, known as the ventricles, which pump blood out of the heart. Understanding the structure and function of the atria is fundamental to grasping how the heart operates as a whole in the cardiovascular system.