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Blood Flow and Circulation
Circulation connects organs by moving blood that carries gases, nutrients, waste products and chemical signals.
#Blood connects organs through a moving network
NHLBI describes the circulatory system as the heart and a network of arteries, veins and capillaries carrying blood around the body. Blood delivers oxygen and nutrients that organs need and carries carbon dioxide to the lungs to be breathed out. The heart supplies the pumping action, while its valves help keep flow moving in the intended direction.
Circulation links processes in different places: oxygen entering at the lungs can reach tissues elsewhere. This account explains the network, not whether a person's circulation is adequate. It does not interpret a pulse, blood pressure reading or symptom.
Evidence: NHLBI: the heart
#The lung route and body route are connected
NHLBI traces blood returning from the body into the right atrium, then the right ventricle, which pumps it toward the lungs through the pulmonary artery. After gaining oxygen in the lungs, blood returns through the pulmonary veins to the left atrium and left ventricle. The left ventricle pumps it into the aorta and onward to the body.
Arteries are named for carrying blood away from the heart and veins for carrying it toward the heart, not for how much oxygen they contain. The pulmonary vessels show why that distinction matters. This outline is an introductory route map, not an assessment of an individual's heart anatomy or blood flow.
Evidence: NHLBI: blood flow through the heart
#The heart muscle also needs its own supply
NHLBI explains that the heart muscle needs oxygen and nutrients like other muscles. Coronary arteries branch from the aorta to deliver blood to it. Coronary veins carry blood from the muscle back toward the right atrium, where it joins the route to the lungs.
The heart pumping blood and the heart muscle receiving blood are related but distinct parts of the explanation. Understanding those roles does not establish the cause of chest discomfort or identify a blocked vessel. Mynd supplies general science education, not a cardiac examination or treatment plan.
Evidence: NHLBI: blood flow through the heart
Source note
The sections above were checked against the linked sources. No clinical review has been performed. This is general research education, not a clinical guideline.