Homeostasis

• Homeostasis maintains the internal enviroment, including:

  • Core temperature
  • pH of blood in relation to enzyme activity
• Negative feedback is when deviation is restored to original state
• Islets of Langerhans are clusters of cells in the Pancreas that produce insulin and glucagon
• Alpha cells produce Glucagon
• Beta cells produce Insulin
• Adrenaline is produced in the adrenal glands during fight or flight, releasing more glucose from hydrolysis of glycogen in the liver
• Insulin Regulation:

  • Attaches to receptors on liver/muscle, changing the tertiary structure, resulting in more glucose absorbed via facilitated diffusion
  • Create more protein carriers for more glucose absorption
  • Enzymes convert glucose to glycogen, via glycogenesis
• Glucagon Regulation:

  • Attaches to receptors on the liver
  • Protein activates into adenylate cyclate
  • ATP is converted into cyclic AMP (cAMP)
  • cAMP activates the protein kinase, that hydrolyses glycogen into glucose via glycogenolysis
  • Also activates enzymes converting glycerol and amino acids into glucose via gluconeogenesis
• Adrenaline Regulation:

  • Attaches to liver
  • Protein G is activated, converting ATP into cAMP
  • This activates kinase to hydrolyse glycogen into glucose via glycogenolysis