Which chambers of the heart are referred to as the Atria?

The atria are indeed referred to as the upper chambers of the heart. There are two atria in the heart—the right atrium and the left atrium. These chambers play a crucial role in the cardiac cycle by receiving blood returning to the heart. The right atrium gathers deoxygenated blood from the body via the superior and inferior vena cavas, while the left atrium collects oxygenated blood from the lungs through the pulmonary veins.

Understanding the function and position of the atria is essential for comprehending how blood flows through the heart. The atria receive and temporarily hold blood before passing it into the ventricles, which are the lower chambers responsible for pumping blood out of the heart. The differentiation between the chambers is key, as it highlights the structural and functional roles each part of the heart plays in overall circulation. The concept that the atria are the upper chambers is fundamental knowledge in cardiology and provides a basis for understanding subsequent topics related to heart function and pathology.