Welcome to: The Anatomy of the Heart.
Your heart is located in the center of your chest.
Its muscular walls contract, which
creates your heartbeat and pumps blood throughout your body.
As your blood moves around, it delivers oxygen and nutrients to every cell.
A normal, healthy adult heart is about the same size as a clenched fist.
Every heart has four chambers.
These are: the right atrium, the right ventricle,
the left atrium, and the left ventricle.
The two upper chambers or atria, receive blood.
The two lower chambers or ventricles pump blood.
Blood returning from your body's organs and
tissues enters the right atrium.
Because this blood has provided oxygen to your body,
it's very oxygen-poor.
It moves to the right ventricle and out to the lungs to
pick up more oxygen in a process called gas exchange.
The now oxygen-rich blood
travels into the left atrium and into
the left ventricle before your heart
pumps it to the rest of the body.
Each chamber is separated by the cardiac muscle and valves.
The valves effectively move blood throughout the heart by opening in only one direction.
This forces the blood to pass through
the chambers, into the lungs, and into
your body without backing up or flowing backward.
Watch as the valves open and close between the atria and the ventricles.
The atrioventricular, or AV, valves are
between the atria and the ventricles on each side of the heart.
They are the tricuspid and the bicuspid, or mitral, valve.
The tricuspid is on the right side and the bicuspid, or mitral, is on the left side.
There are also two semilunar valves: the pulmonary and the aortic.
The pulmonary is between the right
ventricle and the pulmonary trunk, and
the aortic is between the left ventricle and the aorta.
When the AV valves close, they prevent blood from flowing back
into the atria while the ventricles are contracting.
The tricuspid has three flexible cusps or flaps, and the bicuspid has two.
Chordae tendineae are attached to
the papillary muscles, which are located in the ventricles.
When these muscles contract, the white, string-like,
chordae tendineae become taught.
It is these chordae tendineae, together with the
papillary muscles, that keep the valves
shut when the ventricle contracts.
Finally, let's see how all of these
muscles, chambers, and valves work together.
Watch how blood flows through the heart.
This diagram shows the blood entering
the heart from the body.
At this stage, it's oxygen-poor.
After traveling to the lungs, it returns to the heart oxygen rich.
The blood leaving the left ventricle is heading for the body.
This process repeats itself over and over
again to effectively deliver oxygen and
nutrients to your body.
Congratulations!
You've completed: The Anatomy of the Heart.