lungs

• Thorax


  The top part of your body
• Diaphragm


  Muscle that separates the thorax from the abdomen
• Lungs


  • Big
  • Surrounded by pleural membranes
• Ribs


  • Protect the lungs
• Breathing in

  1. Intercostal muscles and diaphragm contract

  2. Thorax volume increases

  3. Pressure decreases, air goes in
• Breathing out

  1. Intercostal muscles and diaphragm relax

  2. Thorax volume decreases

  3. Air is forced out