atrium: Quick Facts

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Facts

Also Known As	atria

Photos

X-ray image of coronary artery circulation

Illustration of a human heart in cross section, showing labeled chambers, valves, and major blood vessels including the aorta, pulmonary trunk, vena cavae, atria, and ventricles.

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.

Illustration of a human heart cross-section showing four chambers-left and right atria and ventricles-with labeled major blood vessels. An inset highlights cardiac muscle tissue, showing myocytes and intercalated disks.

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Topics

interatrial septum auricle atrial fibrillation atrial septal defect chamber ventricle

Male muscle, man flexing arm, bicep curl.

Facts You Should Know: The Human Body Quiz

3d illustration human heart. Adult Anatomy Aorta Black Blood Vessel Cardiovascular System Coronary Artery Coronary Sinus Front View Glowing Human Artery Human Heart Human Internal Organ Medical X-ray Myocardium

Human Organs