Lung Diseases

Asthma:

• Smooth muscle contracts narrowing the airway
• Reduced tidal volume and FEV1
• Bronchi and bronchia are narrower restricting air flow
• Less air reaches gas exchange surface
• More mucus so reduces air in and out 
• Reduced diffusion as the concentration gradient is reduced
• The surface area and alveoli is not affected though

Fibrosis:

• Scar tissue develops around…