regulating glucose

• Blood glucose concentration


  The amount of sugar in our bloodstream
• We need a decent amount of sugar in our blood so that our cells have a constant supply of glucose that they can use for respiration
• If the blood glucose concentration gets too high it can start to damage our tissues
• What happens when we eat a big meal with lots of carbohydrates

  1. Carbohydrates broken down in intestines into glucose

  2. Glucose absorbed into bloodstream

  3. Blood glucose concentration increases
• Pancreas


  An organ that sits just behind the stomach
• How insulin regulates high blood glucose

  1. Pancreas releases insulin

  2. Insulin binds to cells

  3. Cells take up glucose from blood

  4. Glucose stored as glycogen
• Blood glucose concentration increases

  Insulin released to decrease it
• Glucagon


  A hormone that increases blood glucose
• How glucagon regulates low blood glucose

  1. Pancreas releases glucagon

  2. Glucagon binds to liver cells

  3. Liver breaks down glycogen into glucose

  4. Glucose released into blood
• Blood glucose concentration decreases


  Glucagon released to increase it
• Insulin and glucagon


  • Create a negative feedback loop to keep blood glucose at the right level
  • Constantly fluctuate to maintain normal blood glucose