The left and right ventricles are the two larger lower chambers of the heart, while the left and right atriums are its two smaller upper chambers. Blood flow into and out of these chambers is controlled by four valves, which function as doors in a particular order.
To contract and relax the heart muscle, the cardiac conduction system emits electric impulses. These pulses control how quickly and rhythmically your heart beats.
Lets see what happens when blood travels through the heart and lungs:
1. The right atrium is where the blood first enters. The tricuspid valve then allows the blood to enter the right ventricle.
2. Blood is forced into the pulmonary artery by the ventricle when it contracts, passing via the pulmonic valve.
3. Blood is transported through the pulmonary artery to the lungs, where it "picks up" oxygen.
4. It then exits the lungs and travels through the pulmonary vein back to the heart.
Blood flows into the left atrium. It enters the left ventricle through the mitral valve.
5. Blood is then pumped from the left ventricle into the aorta through the aortic valve. The aorta is the artery that supplies blood to the rest of the body.
6. The superior vena cava and inferior vena cava are two significant blood arteries that carry blood back to the heart from the body. Due to the fact that this blood is returning from the body, where oxygen was consumed, it contains less oxygen.
7. Blood is pumped by the vena cava into the right atrium, and the cycle repeats.