Which cavities are part of the thoracic cavity?

Which cavities are part of the thoracic cavity?

• A. Pleural cavities and mediastinum
• B. Pleural cavities only
• C. Mediastinum only
• D. Pericardial cavity and pleural cavities

Answer: (A)

The thoracic cavity is divided into two pleural cavities, each surrounding a lung, and the mediastinum, the central compartment that houses the heart and great vessels (along with other structures like the trachea and esophagus). The pericardial cavity is a small space around the heart that sits inside the mediastinum, so it isn’t counted as a separate major subdivision of the thoracic cavity. Therefore, the cavities that make up the thoracic cavity are the pleural cavities and the mediastinum.

The thoracic cavity is divided into two pleural cavities, each surrounding a lung, and the mediastinum, the central compartment that houses the heart and great vessels (along with other structures like the trachea and esophagus). The pericardial cavity is a small space around the heart that sits inside the mediastinum, so it isn’t counted as a separate major subdivision of the thoracic cavity. Therefore, the cavities that make up the thoracic cavity are the pleural cavities and the mediastinum.