Alveoli

Description

A 3D model of the pulmonary alveoli, showing the grape-like clusters of air sacs at the terminal end of the bronchial tree where gas exchange occurs. Alveolar walls are thin, lined with type I pneumocytes that form the respiratory surface and type II pneumocytes that produce surfactant. The capillary network wraps tightly around each alveolus, bringing deoxygenated blood within a fraction of a micrometer of the air space. The alveolar-capillary membrane is the site of oxygen and carbon dioxide exchange. Oxygen diffuses from the alveolar air space across the membrane into the pulmonary capillary blood, while carbon dioxide moves in the opposite direction. The surface area involved is immense, roughly 70 square meters in total across both lungs. Alveolar anatomy is a core topic in respiratory physiology and pulmonology. The model supports teaching about gas exchange mechanics, surfactant function, and conditions like emphysema or pneumonia where alveolar structure breaks down. Medical advisory board reviewed. Ready for rendering, real-time, and 3D printing.