Anatomy of the Heart Quiz

The heart is about the size of a fist, positioned near the midline of the chest, within the mediastinum.

The apex is the pointed inferior tip of the left ventricle, while the base is the superior aspect.

The pericardium is a triple-layered membrane that surrounds and protects the heart. The fibrous pericardium is the outermost layer and anchors the heart to the mediastinum.

The serous pericardium is a double layer with the parietal layer attached to the fibrous pericardium and the visceral layer (epicardium) directly attached to the heart.

The pericardial cavity is the space between the parietal and visceral layers of the serous pericardium, filled with pericardial fluid.

The epicardium is the outermost layer of the heart, composed of visceral pericardium, fibroelastic tissue, and adipose tissue.

The myocardium is the middle layer of the heart and is responsible for the heart's pumping action.

The endocardium is the innermost layer of the heart lining the chambers and valves.

The middle layer of the heart, composed of cardiac muscle tissue, responsible for the forceful contractions that pump blood.

The innermost layer of the heart, lining the chambers and providing a smooth surface for blood flow.

Two upper chambers of the heart that receive blood returning from the body.

Two lower chambers of the heart that pump blood out to the lungs and the rest of the body.

The valve between the right atrium and right ventricle, consisting of three flaps.

A small flap on the anterior surface of the atria that expands their capacity to hold blood.

A groove on the heart's surface marking the boundary between the atria and ventricles, containing the coronary sinus.

The thin wall separating the right and left atria, containing a remnant of an opening in the fetal heart that closes during infancy.

These fibrous rings are crucial for the proper function of heart valves, providing structural support and preventing overstretching. They act as a "skeleton" for these valves.

These specific rings are responsible for the proper operation of the atrioventricular valves, ensuring blood flows correctly from the atria to the ventricles.

Heart valves open and close in response to changes in blood pressure, ensuring blood flows in one direction through the heart.

The aortic and pulmonary valves are known as semilunar valves because their shape resembles a half-moon.

The tricuspid and bicuspid valves are called atrioventricular valves because they are located between the atria and the ventricles.

The AV valves close during ventricular contraction, preventing blood from flowing back into the atria. They open during atrial contraction allowing blood to flow into the ventricles.

The heart is a double pump system. The right pump deals with deoxygenated blood, while the left pump handles oxygenated blood.

Arteries and veins that supply blood to the heart muscle itself are known as the coronary circulation.

Arteries that encircle the heart like a crown, supplying oxygenated blood to the heart muscle.

Connections between two supply arteries, providing backup blood flow to the heart muscle.

Veins that collect deoxygenated blood from the heart muscle and return it to the right atrium.

A surgical procedure to bypass a blocked coronary artery, using a healthy blood vessel from elsewhere in the body.

These specialized heart fibers are self-excitable, meaning they can initiate and maintain the heart's rhythm.

The heart's natural pacemaker, setting the rhythm of the heartbeats. Located in the right atrium.

Located in the interatrial septum, it slows down the electrical signal to allow the atria to empty before the ventricles contract.

The pathway that carries the electrical signal from the AV node to the ventricles, stimulating their contraction.

The chordae tendineae are tough, fibrous cords that connect the papillary muscles to the cusps of the atrioventricular (AV) valves. They help to prevent the valves from prolapsing (bulging) into the atria during ventricular contraction.

Papillary muscles are cone-shaped muscles located in the ventricles; they attach to the chordae tendineae, which in turn are attached to the atrioventricular valves. These muscles help regulate the opening and closing of the valves to ensure blood flows in the correct direction.

The interventricular septum is a thick muscular wall that separates the left and right ventricles. It helps to prevent blood from mixing between the two sides.

The pulmonary valve is a semilunar valve located at the exit of the right ventricle. It opens to let blood flow into the pulmonary arteries and closes to prevent backflow into the ventricle.

The bicuspid valve, also known as the mitral valve, is an atrioventricular (AV) valve located between the left atrium and left ventricle. It has two cusps that open to allow blood to flow from the atrium to the ventricle and then close prevent backflow into the atrium.

The aortic valve is a semilunar valve located at the exit of the left ventricle. It opens to allow blood flow into the aorta and closes to prevent backflow into the ventricle.

The thickness of the heart muscle (myocardium) varies depending on the chamber's role. The atria have thinner walls because they only need to pump blood a short distance to the ventricles. The ventricles, especially the left ventricle, have thicker walls because they need to generate more pressure to pump blood to the lungs (right ventricle) or the rest of the body (left ventricle).

The fibrous skeleton is a dense connective tissue network within the heart walls. It provides structural support for the heart valves and acts as a point of attachment for cardiac muscle fibers. The fibrous skeleton also prevents over-stretching of the heart valves and helps conduct electrical impulses through the heart.

Large-diameter fibers that conduct action potentials throughout the ventricles, ensuring simultaneous contraction of all ventricle cells.

A recording of the electrical activity of the heart, showing different waves representing depolarization and repolarization of the atria and ventricles.

The first sound of the heart, caused by the closure of the atrioventricular valves at the start of ventricular contraction.

The second sound of the heart, caused by the closure of the semilunar valves at the beginning of ventricular relaxation.

A tough, fibrous sac surrounding the heart, providing protection and anchoring it to the mediastinum.

The inner layer of the pericardium, composed of two membranes with a fluid-filled space between them.