Lungs

• What systems are linked to health in this specification?

  Cardiovascular and respiratory systems
• What are the main components of the respiratory system?

  • Lungs
  • Trachea
  • Bronchi
  • Bronchioles
  • Alveoli
  • Lymph nodes
  • Lymphatic vessels
• What is the primary function of the lungs?

  Gas exchange in humans
• What holds the trachea open?

  C-shaped rings of cartilage
• What do bronchi branch off from?

  The trachea
• What is the role of cartilage in the trachea and bronchi?

  To maintain the airway open
• What type of epithelium lines the trachea?

  Ciliated epithelium
• What do goblet cells produce?

  Mucus
• What is the function of cilia in the respiratory system?

  To move mucus out of the lungs
• What are the steps of ventilation in the lungs during inspiration?

  1. Diaphragm contracts and flattens
  2. External intercostal muscles contract
  3. Rib cage moves up and out
  4. Lung volume increases
  5. Pressure in lungs decreases
  6. Air is drawn into lungs
• What are the steps of ventilation in the lungs during expiration?

  1. Diaphragm relaxes and domes
  2. External intercostal muscles relax
  3. Rib cage moves down and in
  4. Lung volume decreases
  5. Pressure in lungs increases
  6. Air is forced out of lungs
• What is COPD?

  A group of lung conditions affecting expiration
• What does chronic mean in the context of COPD?

  It is a long-term condition
• What happens to the alveoli in emphysema?

  They are broken down, reducing surface area
• What is fibrosis in the lungs?

  Thickening of epithelial tissue in lungs
• What is a common symptom of COPD related to oxygen levels?

  Decreased levels of oxygen in blood
• Why does breathing rate increase in COPD?

  To compensate for reduced gas exchange
• What is a risk factor for COPD related to environmental exposure?

  Exposure to air pollution
• What device measures blood oxygen saturation?

  Finger pulse oximeter
• What is the normal blood oxygen saturation percentage?

  Above 92%
• How is respiratory rate measured?

  By counting breaths per minute
• What is the normal respiratory rate range for adults?

  12 to 20 breaths per minute
• What is the normal body temperature range for adults?

  36.5°C to 37.2°C
• What are the functions of the lymphatic system?

  • Remove excess tissue fluid
  • Drain fluid back into blood circulation
  • Play a role in immune response
• What is lymph?

  Fluid inside lymphatic capillaries
• What do lymph nodes do?

  Filter lymph as it passes through
• What happens to lymph nodes during an immune response?

  They swell due to increased white blood cells
• What is tissue fluid and how is it formed?

  • Bathes all cells in the body
  • Formed when blood enters capillary networks
  • High hydrostatic pressure forces fluid out
• What is the role of plasma proteins in blood capillaries?

  They create low water potential to draw water back
• What is oedema?

  A build-up of tissue fluid causing swelling
• What are the components of tissue fluid?

  • Water
  • Dissolved oxygen
  • Nutrients (glucose, amino acids)
• What is the process of gas exchange in the lungs?

  1. Air enters alveoli
  2. Oxygen diffuses into blood
  3. Carbon dioxide diffuses into alveoli
  4. Gases exchanged during ventilation