The pulmonary plexus is a weblike network of nerve fibers that surrounds the primary bronchi and enters the lungs at the hilum. It consists of both sympathetic and parasympathetic fibers.

A. True
B. False

A. True

Explanation:

Actually, there are two types of pulmonary plexus i.e., the anterior pulmonary plexus that lies right in front of the lungs as well as the posterior pulmonary plexus that lies behind the lungs. The both are related to the hilum i.e., the root of the lungs. The posterior pulmonary plexus innervates wit the lung and accounts for about 75% of the whole pulmonary innervation.

The statement is true.

Explanation:

The lung is innervated by afferent sensory pathways (afferent plexus fibers received from the mucous membranes of the bronchioles and alveoli) and efferent motors (the efferent fibers of the plexus innervates the bronchial musculature), that is, the plexus is made up of sympathetic (from the sympathetic trunk) and parasympathetic (from the vagus nerve) fibers. The vagus nerves and sympathetic thoracic ganglia 4th and 5th contribute fibers that form the anterior and posterior pulmonary plexuses in the pulmonary hilum. Two nerve networks emerge from these plexuses, the peribronchial and periarterial plexuses. The peribronchial plexus is itself divided into extrachondral (between the cartilage and the adventitia) and subchondral (between the cartilage and the epithelium). Some ganglion cells are distributed in the peribronchial plexus, mainly arranged in the extrachondral plexus.

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