PHYL2001 Lecture Notes - Lecture 8: Pulmonary Pleurae, Lung Volumes, Drug Metabolism
Document Summary
The lungs have a lot of functions but the main. Gas exchange between alveoli and blood in the pulmonary capillaries: oxygen, carbon dioxide (moves out of the lungs) Respiratory passways trachea where the air goes down. Pleurae: (membranes surrounding the lungs and the chest) Functions: reduction of friction between the lungs and the chest during inspiration and expiration, creation of pressure gradient, compartmentalisation. The passage ways become thinner and thinner. The bronchus: fibrous coat, smooth muscle layer, basement layer, epithelial layer with cilia on it. Lose muscle and fibrous layer as you go down the passage ways. The alveoli site of gas exchange hence we need a thin membrane: diffusion slow process hence to maximise it, we want thin membranes. Made up of the conducting zone and respiratory zone. As you go down in branching there is an increase in the total cross sectional area. Respiratory zone: site of gas exchange.
