Exam qs

• Give two reasons why pancreas transplants are not used for the treatment of type II diabetes (2)

  • type II produce insulin
  • cells / receptors are less sensitive / responsive to insulin
  • treated by diet / exercise
• Describe the role of the hormone glucagon in the control of blood sugar concentration. (5)

  • Binds to (specific) receptor
  • On muscle / liver cell
  • Activation of enzymes (in liver)
  • Hydrolysis of glycogen
  • (Facilitated) diffusion of glucose out of (liver cells) cells
  • Increases blood glucose levels;
• Describe how insulin reduces the concentration of glucose in the blood. (4)

  • insulin binds to specific receptors (on membranes)
  • insulin activates carrier proteins / opens channels / causes more channels to form
  • insulin increases the permeability of liver / muscle cells / tissues to glucose
  • insulin action results in glucose conversion to glycogen / glycogenesis
• Binding of insulin leads to an increase in the rate of respiration in cells. Explain why (2).

  • insulin leads to more transport proteins for glucose
  • more glucose enters cell