circulation: Quick Facts

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Silhouette diagram of the human body highlighting the heart and major blood vessels, with labeled arteries in red and veins in blue to show the structure of the cardiovascular system.

Diagram of the human circulatory system showing major arteries in red and veins in blue, with labeled pathways for arterial supply and venous drainage to organs including the heart, lungs, liver, kidneys, intestines, and lower limbs.

Watch red blood cells travel through arteries and capillaries to deliver oxygen

Examine the ecologic importance, life cycle, and anatomical structures of the freshwater crustaceans Daphnia

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Topics

pulmonary circulation systemic circulation blood flow cardiac cycle gas transport cytoplasmic streaming How do penguins stay warm?coronary circulation blood Physiology Metabolism death sleep photosynthesis Biological development Excretion nutrition disease Reproduction Senses

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Key People

William Harvey

William Harvey

English physician

Claude Bernard

Claude Bernard

French scientist

Marcello Malpighi

Marcello Malpighi

Italian scientist

DeBakey, Michael

Michael DeBakey

American surgeon

August Krogh

August Krogh

Danish physiologist

Aselli, detail of an engraving by Cesare Bassano, 1623

Gaspare Aselli

Italian physician

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Erasistratus Of Ceos

Greek physician