The diaphragm is the flat, dome-shaped muscle located at the base of the lungs and thoracic cavity.The lungs are enclosed by the pleurae, which are attached to the mediastinum.To this end, the lungs exchange respiratory gases across a very large epithelial surface area—about 70 square meters—that is highly permeable to gases.
The parasympathetic system causes bronchoconstriction, whereas the sympathetic nervous system stimulates bronchodilation.
Reflexes such as coughing, and the ability of the lungs to regulate oxygen and carbon dioxide levels, also result from this autonomic nervous system control.
The nerves then follow the bronchi in the lungs and branch to innervate muscle fibers, glands, and blood vessels.
Each lung is enclosed within a cavity that is surrounded by the pleura.
An interlobular septum is a wall, composed of connective tissue, which separates lobules from one another.
The blood supply of the lungs plays an important role in gas exchange and serves as a transport system for gases throughout the body.
Once the blood is oxygenated, it drains from the alveoli by way of multiple pulmonary veins, which exit the lungs through the hilum.
Dilation and constriction of the airway are achieved through nervous control by the parasympathetic and sympathetic nervous systems.
Sensory nerve fibers arise from the vagus nerve, and from the second to fifth thoracic ganglia.
The pulmonary plexus is a region on the lung root formed by the entrance of the nerves at the hilum.