Diaphragm

• What exactly is the diaphragm

  A thin sheet of muscle below the lungs that separates the thoracic cavity from the abdominal cavity
• What happens to diaphragm when relaxed

  It forms a dome that bulges upwards into the chest cavity to facilitate exhalation
• What happens to the diaphragm when contracted 


  It moves downwards and becomes less arched to facilitate inhalation