gas exchange in the lungs

• What is the primary function of the lungs in the circulatory system?

  To facilitate gas exchange by collecting oxygen and releasing carbon dioxide
• How does the heart interact with the lungs in the circulatory system?

  The heart pumps blood to the lungs to collect oxygen
• What is the name of the tube through which air passes into the lungs?

  The trachea
• What is a key feature of the trachea that prevents it from collapsing?

  It contains rings of cartilage
• What are the two smaller tubes that the trachea splits into?

  The bronchi
• What are the tiny air sacs at the end of the bronchioles called?

  Alveoli
• What is the primary role of the alveoli in the lungs?

  They are the sites of gas exchange
• How does the structure of alveoli facilitate gas exchange?

  They have thin walls and a large surface area
• Why is it important that the alveoli have a good blood supply?

  It ensures that oxygen is rapidly removed, maintaining a steep concentration gradient
• What happens to the concentration gradient when oxygen diffuses into the blood?

  The concentration gradient becomes steeper
• How does breathing affect the rate of diffusion in the lungs?

  Breathing brings fresh oxygen in and removes carbon dioxide, increasing concentration gradients
• What are the adaptations of the alveoli for efficient gas exchange?

  • Millions of alveoli provide a large surface area
  • Very thin walls for a short diffusion path
  • Good blood supply to maintain concentration gradients
• What is the overall process of gas exchange in the alveoli?

  1. Oxygen diffuses from the air into the bloodstream
  2. Carbon dioxide diffuses from the bloodstream into the air
• What should you remember about the adaptations of the lungs for gas exchange?

  • Key adaptations include surface area, wall thickness, and blood supply
  • Important for exam questions