the lungs

• Lungs are adapted for exchanging gases
• The lungs are a complicated process for large animals like humans to exchange gases
• You need to get oxygen from the air into your bloodstream to supply your cells with respiration
• You also need to get rid of the carbon dioxide produced by your cells
• Purpose of the lungs

  To exchange gases between the air and the blood
• Gas exchange in the lungs

  1. Oxygen from the air diffuses into the bloodstream

  2. Carbon dioxide from the blood diffuses into the air
• The lungs


  • Located in the thorax
  • Protected by the ribcage
  • Surrounded by the pleural membranes
  • Contain millions of alveoli
• The air you breathe in goes through the trachea, which splits into bronchi, which split into bronchioles, which end at the alveoli where gas exchange takes place
• The alveoli are surrounded by a network of blood capillaries where gas exchange happens
• Blood reaching the body cells

  Oxygen is released from the red blood cells and diffuses into the body cells, while carbon dioxide diffuses out of the body cells into the blood
• The blood then carries the carbon dioxide back to the lungs