The Heart
The heart is a hollow muscle roughly the size of your fist, and its whole design is built around one job: pushing blood in one direction, over and over, for a lifetime. Learn it as two pumps side by side — a right side that sends blood to the lungs and a left side that sends it to the rest of the body — each with a collecting chamber on top and a pumping chamber below, and a valve guarding every exit. Get the four chambers and four valves straight first, and everything else about circulation clicks into place.
Practice this set for free — no account needed. Loads 16 flashcards into the learner.
Practice in the free learnerHow to study this set
Trace one drop of blood through the heart in order: right atrium, tricuspid valve, right ventricle, pulmonary valve, then back from the lungs into the left atrium, mitral valve, left ventricle, aortic valve. Following the path in sequence fixes both the chambers and the valves at once, because each valve is simply the door out of the chamber before it.
All 16 flashcards
What is the main job of the heart?
To pump blood continuously around the body
What type of tissue is the heart mostly made of?
Muscle — specifically cardiac muscle
This lets it contract rhythmically without tiring.
What is the muscular tissue of the heart wall called?
The myocardium
How many chambers does the human heart have?
Four
What are the two upper chambers of the heart called?
The atria — the right atrium and the left atrium
What are the two lower chambers of the heart called?
The ventricles — the right ventricle and the left ventricle
Which chamber receives deoxygenated blood returning from the body?
The right atrium
Which chamber pumps deoxygenated blood to the lungs?
The right ventricle
Which chamber receives oxygenated blood returning from the lungs?
The left atrium
Which chamber pumps oxygenated blood out to the whole body?
The left ventricle
It has the thickest, most muscular wall because it pumps blood the furthest.
What is the wall of muscle that separates the left and right sides of the heart called?
The septum
What is the purpose of the heart’s valves?
To keep blood flowing in one direction and prevent it from flowing backwards
Which valve lies between the right atrium and the right ventricle?
The tricuspid valve
Which valve lies between the left atrium and the left ventricle?
The mitral valve (also called the bicuspid valve)
Which valve controls blood leaving the right ventricle towards the lungs?
The pulmonary valve
Which valve controls blood leaving the left ventricle into the aorta?
The aortic valve
What to learn next
You can now follow blood through the pump itself. Level 2, "Blood Vessels & Circulation", follows that blood out into the arteries, capillaries and veins that carry it to every cell and back.
Continue to Level 2: Blood Vessels & Circulation →