Parts

#1: The septum - a thick wall of muscle that separates the left and right sides of the heart.

#2: The tricuspid valve - it lets blood flow from the atria to the ventricles, it is a heart valve.

#3: The ventricles - the chambers on the bottom of the heart, they squirt blood into the lungs and body.

#4: The atrium - the two chambers on the top on the heart, and they are for blood.

#5: The aortic valve - it controls the blood as it leaves the heart.