diabetes and control of blood glucose

Question 1

which organ maintains BGC

Answer 1

the liver

Question 2

what does the liver do to blood glucose

Answer 2

converts excess blood glucose into INSOLUBLE compound glycogen

Question 3

describe the process that happens when the blood glucose is increased and where it happens

Answer 3

• pancreas detects a rise in blood glucose conc
  -pancreas(beta cells) secretes insulin into the bloodstream
  -insulin attaches to specific receptors on the surface of the target cells (liver and muscles)

Question 4

what does insulin do to the permeability of target cells to glucose

Answer 4

-stimulates the inclusion of more specific Chanel proteins In the membrane , allowing glucose to enter by diffusion

-which reduces blood glucose concentration

Question 5

what does insulin do with enzymes

Answer 5

-activates enzymes in liver that convert glucose into glycogen

-excess glucose is converted to fat when glycogen stores are full

-these mechanisms cause the blood glucose concentration to decrease , inhibiting insulin production by negative feedback (because insulin lower bgc)

Question 6

describe what happens when theres a decrease in BGC

Answer 6

-detected by pancreas
-alpha cells in pancreas secrete glucagon into the blood
-glucoagn attaches to specific receptors on the surface of target cells in the liver
-which activates enzymes that hydrolyse glycogen into glucose
-glucose is then released into the blood

Question 7

what happens when the demand for glucose is too high

Answer 7

(during marathons) glucagon activates enzymes whihc convert glycerol and amino acids into glucose

-which is released into the blood

-these mechanisms cause BGC to increase , inhibiting glucagon secretion by negative feedback

Question 8

when is adrenaline secreted by the adrenal glands

Answer 8

-when blood glucose levels are too low ( during exercise)

Question 9

describe the mechanism of adrenaline

Answer 9

-attatches to receptors on the surface of specific target cells of the liver and muscles
-activates enzymes that hydrolyse glycogen into glucose
-glucose is released into the blood , providing glucose to cells for respiration

Question 10

Using your knowledge of the kidney, explain why glucose is found in the urine of a person
with untreated diabetes.

Answer 10

-theres a high conc of glucose in the blood
-not all the glucose is reabsorbed into the pct
-carrier /channel proteins are working at maximum rate

Question 11

When insulin binds to receptors on liver cells, it leads to the formation of glycogen from
glucose. This lowers the concentration of glucose in liver cells.
Explain how the formation of glycogen in liver cells leads to a lowering of blood glucose
concentration.

Answer 11

-the concentration of glucose in the cell is lower than in the blood plasma

-creating a glucose concentration gradient

-so glucose is facilitated diffusion into the cells by a channel protein from the blood