What is a common characteristic of emphysema?

A common characteristic of emphysema is the destruction of alveolar walls. Emphysema is a chronic lung condition that primarily affects the alveoli, the small air sacs in the lungs responsible for gas exchange. When the alveolar walls are damaged, they lose their elasticity and surface area, leading to decreased efficiency in oxygen and carbon dioxide exchange. This destruction results in larger, less effective air spaces that impair the lungs' ability to function properly, contributing to symptoms like shortness of breath and reduced exercise tolerance.

Understanding this characteristic is essential for recognizing how emphysema affects respiratory function and the overall health of individuals living with the condition. The other options describe concepts that do not align with emphysema's pathological features; for instance, lung capacity typically decreases, air spaces become enlarged rather than reduced, and gas exchange usually worsens.