Heart

Pericardium: the membrane enclosing the heart, consisting of an outer fibrous layer and an inner double layer of serous membrane

Right and left atrium: The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-poor blood to the lungs. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle. The left ventricle pumps the oxygen-rich blood to the body.

Right and left ventricles: Blood enters the right atrium and passes through the right ventricle. The right ventricle pumps the blood to the lungs where it becomes oxygenated. The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium. From the left atrium blood flows into the left ventricle.

Apex: helps pump or “wring out” blood from the ventricles to the rest of the body 

Ventricular septum:  separates the ventricles and allows for proper blood flow through the heart

Papillary muscles: muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (also known as the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole (or ventricular contraction).

Chordae tendinae: an important role in ventricular contraction by maintaining the continuity in between the different components of the mitral valve complex with proper tension.

Tricuspid, bicuspid, and semilunae valves: the tricuspid valve and mitral (bicuspid) valve. They are located between the atria and corresponding ventricle. Semilunar valves: The pulmonary valve and aortic valve. They are located between the ventricles and their corresponding artery, and regulate the flow of blood leaving the heart.