exchange in human

• How are breathing and respiration different?

  Breathing is air movement; respiration is energy release
• What is the scientific term for breathing?

  Ventilation
• What is gas exchange?

  Diffusion of oxygen and carbon dioxide
• What are the two large structures in the human gas exchange system?

  The left and right lung
• What is the function of the trachea?

  It serves as the windpipe for air passage
• What supports the trachea's structure?

  C-shaped cartilage rings
• What are bronchi and bronchioles?

  Branches of the trachea leading to lungs
• What are alveoli?

  Air sacs at the end of bronchioles
• What is the role of the diaphragm in ventilation?

  It contracts and relaxes to change lung volume
• What does antagonistic mean in muscle pairs?

  One muscle contracts while the other relaxes
• What happens during inhalation?

  External intercostal muscles contract
• What is the effect of external intercostal muscles contracting?

  It increases thoracic volume for inhalation
• What occurs during exhalation?

  Internal intercostal muscles contract
• How does lung pressure change during inhalation?

  Lung pressure decreases as volume increases
• What causes air to flow into the lungs during inhalation?

  Higher atmospheric pressure compared to lung pressure
• What happens to the diaphragm during exhalation?

  It relaxes and returns to a domed position
• How many alveoli are in the human lungs?

  About 300 million
• What adaptations do alveoli have for gas exchange?

  Large surface area, thin walls, and capillary network
• How does the concentration gradient aid gas exchange?

  Blood flow maintains low oxygen concentration
• What are the key processes of ventilation in humans?

  • Inhalation:
  • External intercostal muscles contract
  • Diaphragm contracts and flattens
  • Lung volume increases, pressure decreases
  • Exhalation:
  • Internal intercostal muscles contract
  • Diaphragm relaxes and domes
  • Lung volume decreases, pressure increases
• What are the conditions necessary for effective gas exchange in alveoli?

  • Large surface area
  • Short diffusion distance (one cell layer)
  • Maintained concentration gradient