Alveoli

• What are the small air sacs in the lungs called?

  Alveoli
• What is a key feature of alveoli that aids in gas exchange?

  They have thin walls
• Why is a good blood supply important for alveoli?

  It ensures efficient gas exchange
• What gas is removed from the blood in the alveoli?

  Carbon dioxide (CO₂)
• How does the concentration gradient in the alveoli facilitate gas exchange?

  It allows oxygen to diffuse into the blood
• What is the relationship between surface area and diffusion in alveoli?

  Large surface area enhances diffusion
• Why do alveoli have a steep concentration gradient for oxygen?

  Breathing maintains high oxygen concentration
• How does blood supply affect oxygen concentration in the blood?

  It removes oxygen, maintaining a low concentration
• What are the key features of alveoli that facilitate gas exchange?

  • Thin walls for short diffusion distance
  • Large surface area for diffusion
  • Excellent blood supply for efficient gas exchange
  • Breathing maintains steep concentration gradient