# Heart & Blood Circulation

Describe the circulatory system in detail: the heart has four chambers (two atria, two ventricles) that pump blood in a double loop — one to the lungs for oxygen and one to the rest of the body to deliver it — through arteries, veins, and tiny capillaries

Builds on: Cells, Tissues & Organs (hard, https://ai.page/c/cells-tissues-and-organs/en.md), The Heart & Blood (hard, https://ai.page/c/the-heart-and-blood/en.md)

Concept id: heart-and-blood-circulation. Subject: science. Licence: CC BY-SA 4.0.

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