Thorax
The thorax houses the lungs, heart, great vessels and mediastinum. The rib cage and diaphragm permit ventilation while protecting important structures.
Open interactive lesson & self-check ↗Thorax — learning map
Original conceptual SVG · scalableOriginal schematic relationship map for this topic; relationships are organized for study, not intended as an anatomical depiction or a diagnostic algorithm.
Thoracic wall
The sternum, twelve pairs of ribs and thoracic vertebrae form the framework. Intercostal muscles occupy spaces traversed by neurovascular bundles.
Pleural compartments
Each lung is surrounded by visceral pleura; parietal pleura lines the thoracic cavity. The intervening potential space permits movement with a small volume of fluid.
Mediastinum
The mediastinum lies between the pleural cavities and contains the heart, great vessels, trachea, esophagus, thymic tissue and other structures.
Diaphragm
Contraction flattens the diaphragm and enlarges thoracic volume, contributing to pressure changes that draw air into the lungs.
Reference and next reading
Explore the original curriculum and publisher-hosted resources for full-depth reading; this note is an original schematic introduction, not an exhaustive chapter.