Biochemistry

• Carbon-dioxide and oxygen are exchanged in the alveoli.
• Where does gas exchange occur in the lungs?

  Between the alveoli and blood capillaries
• Why does oxygen diffuse from the alveoli to the capillaries?

  It is in higher concentration in the alveoli
• What is the primary purpose of oxygen in the body?

  It is needed for respiration
• Why does carbon dioxide diffuse from the capillaries into the alveoli?

  It is in higher concentration in the blood
• What reaction produces carbon dioxide in the body?

  Respiration
• What adaptations do alveoli have for efficient gas exchange?

  • Small and numerous, providing a large surface area
  • One cell thick, ensuring a thin diffusion pathway
• What is the significance of the alveoli being small and numerous?

  They provide a large surface area
• Why is it beneficial for alveoli to be one cell thick?

  It ensures the diffusion pathway is thin