Double-Loop Circulation System Diagram - Anatomy & Physiology Reference #3482289 (License: Personal Use)

This black-and-white line drawing depicts a simplified double-loop circulatory system, likely representing a bird or mammal heart, with four labeled chambers: a (right ventricle), b (right atrium), c (left atrium), and d (left ventricle). Arrows indicate deoxygenated blood flowing from b → a → lungs (pulmonary loop), then oxygenated blood returning via c → d → body (systemic loop). Shading denotes blood volume and directionality, emphasizing separation of oxygenated and deoxygenated streams.

Used in biology and medical education to teach cardiovascular physiology, especially comparative anatomy of vertebrate circulatory systems. Matches user intent for academic study, lecture preparation, or visual aid in explaining heart function and blood flow dynamics.