The lungs

• Lungs


  Organ that gets oxygen into your bloodstream and removes carbon dioxide from your blood
• Thorax


  • The top part of your body
  • Separated from the lower part of the body by the diaphragm
  • The lungs are protected by the ribcage
  • Surrounded by the pleural membranes
• Air flow in the lungs

  1. Air breathed in goes through the trachea

  2. Trachea splits into two bronchi, one going to each lung

  3. Bronchi split into progressively smaller bronchioles

  4. Bronchioles end at alveoli where gas exchange takes place
• Alveoli


  Small air sacs in the lungs where gas exchange occurs
• Gas exchange in the alveoli


  1. Oxygen diffuses from alveoli into blood

  2. Carbon dioxide diffuses from blood into alveoli to be breathed out
• Gas exchange in the body


  1. Oxygen released from red blood cells into body cells

  2. Carbon dioxide diffuses from body cells into blood
• Breathing rate


  The number of breaths per minute
• Breathing rate calculation


  • Bob takes 91 breaths in 7 minutes, his average breathing rate is 13 breaths per minute
• Alveoli are well adapted for carrying out gas exchange