diabetes mellitus

Question 1

what is the normal range for the concentration of glucose in the blood per 100ml

Answer 1

70-110mg

Question 2

what does glucose homeostasis rely on

Answer 2

the antagonist effects of 2 hormones, insulin and glucagon

Question 3

what happens when blood level rises above the normal range

Answer 3

secretion of insulin triggers the uptake of glucose from the blood into the body cells, decreasing the blood glucose concentration

Question 4

what happens when blood glucose level drops below the normal range

Answer 4

secretion of glucagon promotes release of glucose into the blood from energy stores, such as liver glycogen, increasing the blood glucose concentration

Question 5

what happens to the blood glucose level after eating a carbohydrate rich meal

Answer 5

the rising level of insulin promotes synthesis of glycogen from glucose entering the liver in the hepatic portal vein.

Question 6

between meals the blood in the hepatic portal vein has a much lower glucose concentration, what does glucagon stimulate

Answer 6

glucagon stimulates the liver to break down glycogen, convert amino acids and glycerol to glucose and release glucose into the blood

Question 7

insulin and glucagon together ensure that blood exiting the liver has a glucose concentration in the …….…….… range at nearly all times

Answer 7

normal

Question 8

which cells are the only cells that don’t require insulin to take up glucose from the blood

Answer 8

the brain cells - this ensures the brain always has access to circulatory fuel even if supplies are low

Question 9

where are glucagon and insulin produced

Answer 9

the pancreas

Question 10

…….….. cells of pancreatic islets make glucagon

Answer 10

alpha

Question 11

…….….. cells of pancreatic islets make insulin

Answer 11

beta

Question 12

like all hormones, insulin and glucagon are released into the ………… ………………. and then into the blood stream

Answer 12

interstitial fluid

Question 13

in which 2 organ systems does the pancreas function

Answer 13

endocrine (insulin and glucagon) and digestive (secretin induces production of bicarbonate in the pancreas to neutralise the chyme in the small intestine)

Question 14

what is diabetes mellitus caused by

Answer 14

a deficiency of insulin or a decreased response to insulin in target tissues. the blood glucose level rises but the cells are unable to take up enough glucose to meet metabolic needs. instead fat becomes the main substrate for cellular respiration

Question 15

in people with diabetes mellitus, the level of glucose in the blood may exceed the capacity of the kidney to reabsorb this nutrient. what does this result in

Answer 15

glucose that remains in the kidney filtrate is excreted. because of this, the presence of sugar in the urine is a test for the disorder

Question 16

what are the 2 main types of diabetes

Answer 16

1 and 2 - both are marked by high blood glucose levels but they have very different causes

Question 17

what is type 1 diabetes

Answer 17

an autoimmune disorder in which the immune system destroys the beta cells of the pancreas. this destroys the persons ability to produce insulin.
treatment consists of insulin injections

Question 18

what is type 2 diabetes

Answer 18

characterized by failure of target cells to respond normally to insulin. insulin is produced but the target cells fail too take up glucose from the blood and blood glucose levels remain high

Question 19

what can increase the risk of developing type 2 diabetes

Answer 19

heredity can play a role
excess body weight
lack of exercise

Question 20

how is type 2 diabetes controlled

Answer 20

by healthy eating and exercise however some require medication