BIOL 221 Lecture Notes - Lecture 7: Bronchopulmonary Segment, Thoracic Cavity, Bronchus
Document Summary
The lungs are located in the thoracic cavity. The right lung has three lobes; the left has two because the heart takes up some of the space on the left. Each lung has a depressed area called the hilum through which primary bronchi enter and blood vessels and nerves enter or leave. Each lobe is served by a secondary (lobar) bronchus and is divided into bronchopulmonary segments. Each bronchopulmonary segments has its own blood supply, nerve supply and tertiary (segmental) bronchus. A bronchopulmonary segment may be surgically removed with limited effect on surrounding segments (obviously, total lung capacity would decrease). Bronchopulmonary segments are further divided into lobules. Serous membranes associated with the lungs are called pleurae (singular = pleura). The visceral pleura covers the lung; the parietal pleura lines the thoracic cavity. The two lungs are physically separated by the mediastinum into two compartments. The thoracic wall consists of the thoracic vertebrae posteriorly.