Human Anatomy — Cardiovascular System

Atrioventricular Node (AV Node)

A node that delays the electrical signal before it passes to the ventricles.

What is the function of the coronary arteries?

They supply oxygenated blood to the heart muscle itself.

Cardiac Output

The volume of blood the heart pumps per minute, calculated as stroke volume times heart rate.

Stroke Volume

The amount of blood ejected by a ventricle during one contraction.

Why is the left ventricular wall thicker than the right?

The left ventricle pumps blood to the entire body, requiring more force than the right ventricle, which only pumps to the lungs.

Pulmonary Circulation

The circulation of blood between the heart and the lungs.

Systemic Circulation

The circulation of blood between the heart and the rest of the body.

Baroreceptors

Sensors located in blood vessels that detect changes in blood pressure.

What is the purpose of the pericardium?

A fibrous sac that surrounds and protects the heart, reducing friction from surrounding structures.

Endocardium

The thin inner lining of the heart chambers and valves.

What causes the first heart sound 'lub'?

The closure of the atrioventricular valves (mitral and tricuspid) at the start of ventricular contraction (systole).

What causes the second heart sound 'dub'?

The closure of the semilunar valves (aortic and pulmonary) at the end of ventricular contraction (diastole).

Arteries

Blood vessels that carry blood away from the heart.

Veins

Blood vessels that carry blood towards the heart.

Capillaries

Microscopic blood vessels where exchange of gases, nutrients, and waste occurs.

Hemodynamics

The study of blood flow and the forces involved in circulation.

What is the Frank-Starling law of the heart?

The principle that the stroke volume of the heart increases in response to an increase in the volume of blood filling the heart.

What is the function of the aortic valve?

Prevents backflow of blood from the aorta into the left ventricle during diastole.

What is the function of the pulmonary valve?

Prevents backflow of blood from the pulmonary artery into the right ventricle during diastole.

Blood Pressure

The force exerted by circulating blood on the walls of blood vessels.

Hypertension

A condition characterized by consistently elevated blood pressure.

Atherosclerosis

The build-up of fats, cholesterol, and other substances in and on the artery walls.

Electrocardiogram (ECG)

A test that measures the electrical activity of the heart.

What is the role of hemoglobin in the cardiovascular system?

Hemoglobin in red blood cells binds to oxygen and transports it from the lungs to tissues throughout the body.

What is the function of the inferior vena cava?

Carries deoxygenated blood from the lower body back to the right atrium of the heart.

What is the function of the superior vena cava?

Carries deoxygenated blood from the upper body back to the right atrium of the heart.

What is the function of the mitral valve?

Prevents backflow of blood from the left ventricle into the left atrium during ventricular contraction.

What is the function of the tricuspid valve?

Prevents backflow of blood from the right ventricle into the right atrium during ventricular contraction.

What is an aneurysm?

An abnormal bulge or ballooning in the wall of a blood vessel.

What is cardiac ischemia?

A condition where the heart muscle does not receive enough oxygen due to reduced blood flow, often caused by a blockage.

What is the role of the papillary muscles?

They contract to prevent inversion or prolapse of the atrioventricular valves during ventricular contraction.