alveoli

Which gases are involved in gas exchange?

• (O₂) (CO₂).

3. How does emphysema affect the alveoli?

• The walls break down, reducing surface area for gas exchange.

4. What is the main cause of cystic fibrosis?

• A faulty inherited gene from both parents.

5. How does the alveoli structure help gas exchange?

• Thin walls, moist surface, large surface area, and a good blood supply.

The main structures involved in gas exchange are:

• Alveoli – Tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged.

• Capillaries – Surround the alveoli and allow gases to move between the blood and lungs.

• Trachea – The windpipe that carries air to the lungs.

• Bronchi & Bronchioles – Airways that branch into the lungs, directing air to the alveoli.

• Diaphragm – Muscle that helps with breathing by contracting and relaxing.

2. Explain what happens during an asthma attack

• The airways become inflamed and narrow.

• Muscles around the airways tighten, making it harder to breathe.

• Mucus builds up, blocking airflow.

• Symptoms include wheezing, coughing, chest tightness, and shortness of breath.

• Common triggers include smoking, air pollution, allergens, and exercise.

3. Describe how emphysema develops over time

• Long-term exposure to irritants (e.g., smoking, air pollution) damages the alveoli.

• The alveoli walls break down, creating larger air spaces instead of many small ones.

• This reduces surface area, making it harder for oxygen to pass into the blood.

• Over time, breathing becomes more difficult, leading to shortness of breath, even at rest.

Asthma - Inhalers (relax airway muscles), avoiding triggers (smoke, allergens), medication to reduce inflammation.

Emphysema - Oxygen therapy, quitting smoking, breathing exercises, medication to open airways.

Cystic Fibrosis - Physiotherapy (clears mucus), antibiotics (prevent infections), enzyme supplements (help digestion), lung transplants in severe cases.

Gas Exchange and Related Conditions:

1. Emphysema Effects: Long-term irritants damage alveoli, reducing surface area for gas exchange, making breathing harder.

2. Cystic Fibrosis: Caused by a faulty inherited gene from both parents, affecting mucus clearance in lungs and digestion.

3. Alveoli Structure: Features such as thin walls, moisture, large surface area, and capillary networks facilitate effective gas exchange.

4. Treatment Options:

   • Asthma: Inhalers, avoiding triggers, anti-inflammatory medications.

   • Emphysema: Oxygen therapy, smoking cessation, breathing exercises.

   • Cystic Fibrosis: Physiotherapy, antibiotics, enzyme supplements, and possible lung transplants.