Overview
This lecture covers the functions, components, and processes of the respiratory system, common disorders, and tips for maintaining respiratory health.
Functions of the Respiratory System
- Transports air into and out of the lungs.
- Protects the body from harmful inhaled particles.
- Responsible for the exchange of oxygen (O2) and carbon dioxide (CO2).
Components of the Respiratory System
- Nose and nasal cavity filter, humidify, and warm incoming air.
- Mouth or oral cavity serves as an alternative air entry.
- Pharynx (throat) connects respiratory openings to the larynx and esophagus; part of both respiratory and digestive systems.
- Larynx (voice box) contains vocal cords.
- Trachea (windpipe) allows air passage to the bronchi.
- Bronchi branch from the trachea into smaller bronchioles.
- Bronchioles connect to alveoli, tiny air sacs where gas exchange occurs.
- Diaphragm muscle contracts and relaxes to enable breathing.
Breathing Process and Gas Exchange
- Air enters through nose/mouth, passes pharynx, and travels through the trachea.
- The epiglottis directs air to trachea and food to esophagus, preventing choking.
- Air moves into bronchi, bronchioles, and then alveoli.
- Oxygen diffuses into blood in alveolar capillaries; CO2 diffuses from blood to alveolar sacs to be exhaled.
- Diaphragm contracts during inhalation allowing lungs to expand, relaxes during exhalation.
Respiratory System Disorders
- Minor disorders: common cold, influenza, acute bronchitis (bronchi inflammation), pneumonia (bronchioles/alveoli inflammation).
- Severe disorders: chronic bronchitis (inflamed/narrow bronchi, often from smoking), emphysema (overstretched alveoli), lung cancer (mainly caused by smoking).
Maintaining Respiratory Health
- Maintain a healthy weight to avoid added lung stress.
- Stay hydrated to keep mucous lining thin and effective.
- Eat foods rich in vitamins, minerals, and antioxidants.
- Limit exposure to allergens like dust, pollen, and animal dander.
- Practice good hygiene to prevent infection.
- Limit alcohol as it dehydrates and weakens immunity.
- Engage in regular aerobic activity.
- Add indoor plants to improve air quality.
Key Terms & Definitions
- Pharynx — throat; connects nose/mouth to larynx and esophagus.
- Larynx — voice box; contains vocal cords.
- Trachea — windpipe; main airway to the bronchi.
- Bronchi — two main tubes branching from trachea into each lung.
- Bronchioles — smaller branches of the bronchi.
- Alveoli — tiny air sacs for gas exchange in the lungs.
- Diaphragm — muscle assisting with breathing.
- Epiglottis — flap preventing food from entering trachea.
Action Items / Next Steps
- Review respiratory system diagram.
- Practice labeling components of the respiratory system.
- Prepare for questions on respiratory functions and health maintenance.