Final answer:
The mediastinum is the central compartment of the thoracic cavity containing the heart, trachea, esophagus, and thymus gland, bordered by the pleural cavities of the lungs.
Step-by-step explanation:
The area between the lungs that contains the heart, trachea, esophagus, and thymus gland is called the mediastinum. This central compartment of the thoracic cavity is surrounded by the pleura of the lungs and extends from the sternum to the vertebral column. It is divided into different areas, with the heart occupying the middle mediastinum.
The thymus gland is a bilobed structure within the anterior part of the mediastinum, encapsulated by connective tissue. The trachea bifurcates into the right and left bronchi as it enters each lung, and the esophagus passes behind the trachea and heart to continue into the abdomen. The pleural cavities are on either side of the mediastinum and house the lungs.