Given your understanding of how healthy lungs work, describe how emphysema disrupts the exchange of oxygen and carbon dioxide between the air and blood.

Emphysema is a type of chronic obstructive pulmonary disease (COPD) that damages the air sacs (alveoli) in the lungs. Here's how it disrupts the exchange of oxygen and carbon dioxide:

1. Healthy Lungs: In healthy lungs, air travels down your windpipe into bronchial tubes and then into smaller tubes (bronchioles) ending in clusters of tiny air sacs. The walls of these air sacs are thin and elastic and are surrounded by capillaries. Oxygen from the air you breathe passes into these blood vessels and enters your bloodstream. At the same time, carbon dioxide, a waste product, moves from the capillaries into the air sacs and is exhaled out.

2. Damage to Alveoli: In emphysema, the walls of the alveoli are damaged. They lose their elasticity and begin to break down. This results in fewer, larger air sacs which decrease the amount of gas exchange surface area.

3. Impaired Gas Exchange: With less surface area, less oxygen can pass into the blood, and it becomes harder for carbon dioxide to be removed. This leads to shortness of breath and other symptoms as your body struggles to get the oxygen it needs and remove excess carbon dioxide.

4. Trapped Air: Furthermore, the damage to the alveoli means that they cannot effectively push out all the air during exhalation. This leads to trapped air in the lungs, which can cause them to become overstretched and can further reduce the effectiveness of gas exchange.

5. Progression: Over time, these problems can lead to lower oxygen levels in the blood and higher carbon dioxide levels, which can cause a range of health problems.