Which circuit sends oxygen-poor blood to the lungs to pick up oxygen?

The pulmonary circuit is responsible for sending oxygen-poor blood to the lungs. This process is crucial for oxygenation, as it allows carbon dioxide to be expelled from the blood and oxygen to be absorbed. The right side of the heart pumps deoxygenated blood into the pulmonary arteries, which then carry it to the lungs. In the lungs, gas exchange occurs in the alveoli, where oxygen enters the blood, and carbon dioxide is released. After this oxygenation process, the now oxygen-rich blood returns to the left side of the heart via the pulmonary veins and is then distributed throughout the body through the systemic circuit.

In contrast, the systemic circuit handles the distribution of oxygenated blood to the rest of the body, the coronary circuit supplies blood specifically to the heart muscle itself, and the portal circuit deals with the transportation of blood from the gastrointestinal tract and spleen to the liver. Each of these circuits has a distinct role in the overall cardiovascular system, making the pulmonary circuit essential for gas exchange and oxygen delivery.