Pleura (or Pleurae) and Pleural Cavity of the Lungs
Last update:
Introduction to Lungs Anatomy
- The soft, elastic lungs occupy most of the thoracic cavity and are protected from injury by the surrounding the
sternum and
rib cage.
- Both
right lung and
left lung rest on the
diaphragm muscle that separates the thoracic and abdominal cavities.
- A large portion of each lung consists of
blood vessels (arteries, veins, & capillaries) and
respiratory tubes (bronchi, bronchioles, & alveolar ducts).
- Most of the lung volume, however, is made of small clusters of alveoli. Each
alveolus is a small, thin-walled, cup-shaped sac that protrudes from the smallest air ducts.
- There are approximately 300 million alveoli in each lung, and they are the regions where gases are exchanged with nearby capillaries.