Circulatory Loops
Put the entire system together by following blood through pulmonary and systemic circulation.
The pulmonary circuit
Pulmonary circulation carries oxygen-poor blood from the right side of the heart to the lungs. In the lungs, blood participates in gas exchange before returning to the left side of the heart.
The systemic circuit
Systemic circulation carries oxygen-rich blood from the left side of the heart toward tissues throughout the body. After exchange at the tissues, oxygen-poor blood returns toward the right side of the heart.
Put the loops together
The two circuits operate continuously. The right side of the heart sends blood toward the lungs, while the left side sends blood into the systemic circulation.
Gas exchange
Blood reaches the lungs so oxygen and carbon dioxide can be exchanged between the blood and respiratory system.
Tissue exchange
At systemic tissues, blood delivers oxygen and nutrients and receives waste products for transport away.
One heart. Two connected circuits.
Pulmonary circulation handles the heart-lung connection, while systemic circulation handles the heart-body connection. Together they form one continuous cardiovascular system.
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