BLOOD FLOW IN THE BODY
If you follow the flow of blood shown in Figure 34.6
you might notice that it flows in two loops. First
To the lungs and back
When blood from the body flows into the right atrium
it has a low concentration of oxygen but a high concentration of carbon dioxide. This deoxygenated blood is dark red. The blood flows from the right atrium into the right ventricle and is pumped into the pulmonary arteries that lead to the lungs
Eventually
blood flows into capillaries in the lungs that are in close contact with the air that comes into the lungs. The air in the lungs has a greater concentration of oxygen than the blood in the capillaries does
oxygen diffuses from the lungs into the blood. At the same time
carbon dioxide diffuses in the opposite direction—from the blood into the air space in the lungs. Oxygenated blood
the left atrium of the heart to be pumped out to the body.
To the body and back
The left atrium fills with oxygenated blood from the lungs
beginning the second loop of the figure eight. As shown in Figure 34.6
BLOOD FLOW IN THE BODY
If you follow the flow of blood shown in Figure 34.6
you might notice that it flows in two loops. First
To the lungs and back
When blood from the body flows into the right atrium
it has a low concentration of oxygen but a high concentration of carbon dioxide. This deoxygenated blood is dark red. The blood flows from the right atrium into the right ventricle and is pumped into the pulmonary arteries that lead to the lungs
Eventually
blood flows into capillaries in the lungs that are in close contact with the air that comes into the lungs. The air in the lungs has a greater concentration of oxygen than the blood in the capillaries does
oxygen diffuses from the lungs into the blood. At the same time
carbon dioxide diffuses in the opposite direction—from the blood into the air space in the lungs. Oxygenated blood
the left atrium of the heart to be pumped out to the body.
To the body and back
The left atrium fills with oxygenated blood from the lungs
beginning the second loop of the figure eight. As shown in Figure 34.6
