Main Functions:
Breathing (Ventilation): Moving air in and out of the lungs.
Gas Exchange: Oxygen enters the blood, and carbon dioxide leaves the blood.
Regulation of Blood pH: Helps control the acid-base balance in the body.
Protection: Filters out harmful particles and pathogens from the air.
How Breathing Works:
• Inhalation: Diaphragm contracts, chest expands, and air enters the lungs.

• Exhalation: Diaphragm relaxes, chest contracts, and air leaves the lungs.
Gas Exchange:
• Oxygen enters the blood in the alveoli.
• Carbon Dioxide leaves the blood and is exhaled.
Common Problems:
• Asthma: Narrowed airways make it hard to breathe.
• COPD: Long-term lung damage, often from smoking.
• Pneumonia: Infection causing lung inflammation.
• Bronchitis: Inflammation of the airways,often due to inflammation.
What is Exchange