Control Of Blood Glucose Conc

Question 1

Key points that I keep forgetting:

Answer 1

Glycogenesis - excess glucose is removed from blood to be converted into glycogen

Glycogenolysis - glucose is released into blood

Rise is blood glucose conc is detected by beta cells
Fall in blood glucose conc detected by alpha cells

Insulin - increases rate of respiration of glucose
Glycogen - decreases rate of respiration of glucose in cells

Adenylate cyclase : converts ATP into chemical molecule called cAMP

Glucose transporter GLUT 4

Question 2

Metformin is a drug commonly used to treat type II diabetes.
Metformin’s ability to lower the blood glucose concentration involves a number of mechanisms including:

. increasing a cell’s sensitivity to insulin
. inhibiting adenylate cyclase.

Explain how increasing a cell’s sensitivity to insulin will lower the blood glucose concentration.

2 marks

Answer 2

1. (More) insulin binds to receptors;
2. (Stimulates) uptake of glucose by channel/transport proteins
   OR
   Activates enzymes which convert glucose to glycogen;

Accept activates enzymes for glycogenesis.
Reject active transport.
Accept carrier proteins or GLUT 4 for channel proteins.
Accept insulin stimulates addition of channel proteins in membranes.

Question 3

Metformin is a drug commonly used to treat type II diabetes.
Metformin’s ability to lower the blood glucose concentration involves a number of mechanisms including:

. increasing a cell’s sensitivity to insulin
. inhibiting adenylate cyclase.

Explain how inhibiting adenylate cyclase may help to lower the blood glucose concentration

2 marks

Answer 3

1. Less/no ATP is converted to cyclic AMP/cAMP;
2. Less/no kinase is activated;
3. Less/no glycogen is converted to glucose
   OR
   Less/no glycogenolysis;

If no indication of less/no for any of the mark points award max 2 marks.
Accept all marks in context of adrenaline.
Ignore gluconeogenesis.