The Cardiovascular System: The Heart Overview

What is the primary function of the heart in the cardiovascular system?

To keep blood moving and maintain homeostasis.

What is the range of blood volume pumped by the heart per minute?

Between 5 and 30 liters.

What is the size of the human heart compared to?

Roughly the size of a clenched fist.

What are the two closed circuits of the cardiovascular system?

The pulmonary circuit and the systemic circuit.

What does the pulmonary circuit do?

Carries carbon dioxide-rich blood from the heart to the lungs and back.

What does the systemic circuit do?

Transports oxygen-rich blood from the heart to the rest of the body and back.

What are the four muscular chambers of the heart?

Right atrium, left atrium, right ventricle, left ventricle.

What is the role of the right and left atria in the heart?

They collect blood returning to the heart.

What is the role of the right and left ventricles in the heart?

They discharge blood into vessels to leave the heart.

What is the pericardium?

The serous membrane lining the pericardial cavity that surrounds the heart.

What are the two layers of the pericardium?

Visceral pericardium (epicardium) and parietal pericardium.

What are the three distinct layers of the heart wall?

Epicardium, myocardium, and endocardium.

What is the function of the myocardium?

It is the cardiac muscle responsible for heart contractions.

Where is the heart located in relation to the midline of the body?

Slightly to the left of the midline.

At what angle does the heart sit in the thoracic cavity?

At an oblique angle to the longitudinal axis of the body.

What are the external sulci of the heart?

They mark the internal boundaries of the heart.

What are the major valves of the heart?

Tricuspid valve, mitral valve, pulmonary valve, and aortic valve.

What is the cardiac cycle?

All of the electrical and mechanical events that take place during one heartbeat.

What does systole refer to in the cardiac cycle?

Contraction of the heart.

What does diastole refer to in the cardiac cycle?

Relaxation of the heart.

What is the role of the autonomic innervation of the heart?

To regulate heart rate and rhythm.

What is the significance of the heart's orientation in the thoracic cavity?

It affects the positioning of the heart's chambers and vessels.

What is the function of the coronary circulation?

To supply blood to the heart muscle itself.

epicardium

covers the outside of the heart

endicardium

lines the insides of the heart

pulmonary circuit

right atrium

tricuspid value

right ventricle

pulmonary value

pulmonary value

systemic circuit

left atrium

mitral valve

left ventricle

aortic valve

aorta