Human Circulation System Diagram - Heart, Lungs, and Blood Vessels Explained #1499030 (License: Personal Use)

This medical illustration depicts the complete human circulatory pathway, including the right and left sides of the heart, pulmonary artery and vein, aorta, and capillary networks in peripheral tissues. Deoxygenated (black/blue) blood enters the right atrium via the precava and postcava, is oxygenated in the lungs via pulmonary capillaries, and returns as arterial (red) blood to the left atrium before being pumped systemically. Key structures like ventricles, atria, and major vessels are clearly labeled for educational clarity.

Used in biology, anatomy, and health education web pages; supports user intent to understand cardiovascular physiology, study for exams, or teach circulation fundamentals.