Respiratory membrane

Definition

The respiratory membrane is a thin barrier through which gas exchange (oxygen in, carbon dioxide out) occurs between the air in the alveoli and the blood in the pulmonary capillaries. It consists of alveolar epithelial cells, capillary endothelial cells, and their shared basement membrane.

Related terms

Alveoli: Tiny air sacs in the lungs where gas exchange with the bloodstream occurs.

Capillaries: Small blood vessels that facilitate the exchange of oxygen, carbon dioxide, and other nutrients and waste products between blood and tissues.

Gas Exchange: The process by which oxygen is taken into the body and carbon dioxide is expelled, occurring primarily in the lungs at the respiratory membrane