gas exchange

• Gas Exchange


  The process of getting oxygen into your bloodstream and getting rid of carbon dioxide
• You need to get oxygen into your bloodstream. You also need to get rid of the carbon dioxide
• Air sacs (alveoli)


  Part of the respiratory system where gas exchange takes place
• Diaphragm


  Muscle that sits underneath the ribcage and moves up when relaxed and down when contracted to help get air in and out of the lungs
• Gas Exchange Happens in the Lungs

  1. Air is inhaled into the lungs

  2. Oxygen in the inhaled air passes into the bloodstream to be used in respiration

  3. Carbon dioxide is a waste product of respiration and passes out of the blood and is then breathed out

  4. Gases pass into or out of the bloodstream by diffusion
• Lungs


  • They're porous to allow gases to pass in and out
  • They have a large surface area to volume ratio to maximise gas exchange
• How the Respiratory System Works

  1. The diaphragm moves up when relaxed and down when contracted to help get air in and out of the lungs

  2. The air that is breathed in goes through the trachea which splits into two bronchi, one going to each lung

  3. The bronchi split into smaller bronchioles

  4. The bronchioles end at small air sacs in the lungs called alveoli where gas exchange takes place
• Blood capillaries (tiny blood vessels) are located near the alveoli in the lungs
• Oxygen passes from the alveoli into the blood capillaries and carbon dioxide passes from the blood capillaries into the alveoli
• Bronchioles


  Smallest airways in the respiratory system that branch off from the bronchi and lead to the alveoli.
• Alveoli


  Tiny air sacs located at the end of the bronchioles where gas exchange occurs between the lungs and the blood.