An alveolus (plural: alveoli, from Latin alveolus, "little cavity") is an anatomical structure that has the form of a hollow cavity. Found in the lung parenchyma, the pulmonary alveoli are the dead ends of the respiratory tree, which outcrop from either alveolar sacs or alveolar ducts, which are both sites of gas exchange with the blood as well. Alveoli are particular to mammalian lungs. Different structures are involved in gas exchange in other vertebrates. The alveolar membrane is the gas-exchange surface. The blood brings carbon dioxide from the rest of the body for release into the alveoli, and the oxygen in the alveoli is taken up by the blood in the alveolar blood vessels, to be transported to all the cells in the body.

Contents

• 1 Location
• 2 Anatomy
• 3 Histology
• 4 Diseases
• 5 Regenerative ability of the human pulmonary alveolus
• 6 Additional images
• 7 References
• 8 External links

Location

The alveoli are located in the respiratory zone of the lungs, at the distal termination of the alveolar ducts and atria. These air sacs are the forming and termination point of the respiratory tract. They provide total surface area of about 100 m.

Adjective

alveolar (not comparable)

Positive alveolar

Comparative not comparable

Superlative none (absolute)

1. Of, or relating to an alveolus
2. (anatomy) Relating to the jaw ridge containing the tooth sockets
3. (anatomy) Relating to the alveoli (small air sacs) of the lungs
4. (phonetics) Formed with the tip of the tongue touching the inner ridge of the gums of the upper front teeth

• alveolar bone
• alveolar ridge