16.3 hormones and the regulation of blood glucose concentration

Question 1

outline the factors which influence blood glucose concentration

Answer 1

• directly from the diet
• glycogenolysis
• gluconeogenesis

Question 2

explain the role of insulin in regulating blood glucose

Answer 2

• detected by hypothalamus
• insulin released from beta cells in the Islet of Langerhans
• glycogenesis
• blood glucose concentration in the blood falls to normal

Question 3

explain the role of glucagon in regulating blood glucose

Answer 3

• detected by hypothalamus
• glucagon released from alpha cells
• from Islets of Langerhans
• glycogenolysis
• gluconeogenesis
• blood concentration of glucose rises to normal

Question 4

explain the roles of adrenaline in regulating blood glucose

Answer 4

• detected by hypothalamus
• adrenaline released by adrenal glands
• glycogenolysis
• blood glucose concentration rises to normal

Question 5

second messenger model

Answer 5

• adrenaline/ glucagon bonds to receptors in the plasma membrane of liver cells
• receptor changes shape
• adenyl cyclase is activated
• ATP -> cyclic AMP
• activates protein kinase enzymes in cell
• so glycogenolysis occurs