Final answer:
The thoracic cavity, positioned above the diaphragm, houses key organs such as the heart within the pericardial cavity and the lungs within the pleural cavities.
Step-by-step explanation:
The thoracic cavity lies just above the diaphragm and contains several organs including the heart and the lungs. The thoracic cavity, an essential part of the ventral cavity, is enclosed by the rib cage and contains not only the lungs but also the heart, which is situated within the mediastinum. The diaphragm forms the lower boundary of the thoracic cavity, creating a separation from the larger abdominopelvic cavity situated beneath it. The thoracic cavity itself is subdivided into three main areas: the left and right pleural cavities, which house the lungs, and the pericardial cavity within the mediastinum that encompasses the heart.