blood glucose homeostasis

Question 1

low blood glucose level stimulates?

Answer 1

secretion of glucagon [a hormone] from alpha cells of pancreatic islets

Question 2

what does the glucagon do- what is overall outcome & what is released

Answer 2

acts on hepatocytes and accelerates glycogenolysis [conversion glycogen - glucose] also promotes formation of glucose from lactic acid & other A.A.
Overall - hepatocytes release glucose into blood +blood glucose level rises [gluconeogenesis]

Question 3

how is the hormone used as negative feedback

Answer 3

once glucose levels continue to rise high blood glucose level [hyperglycaemia] inhibits glucagon to be released

Question 4

function of insulin- what is the outcome of this?

Answer 4

acts on various body cells- accelerates facilitated diffusion of glucose from blood into cell, decreases gluconeogenesis, and glycolysis [conversion of glycogen - glucose, increase protein synthesis, A.A. uptake, fatty acid synthesis and glycogenesis - blood glucose level falls starts again if blood glucose level falls again

Question 5

what else stimulates the release of 2 hormones [insulin + glucagon] apart from blood glucose
what else indirectly stimulates insulin

Answer 5

several hormones and neurotransmitters
growth hormone + adrenocorticotrophic hormone [they act to elevate blood glucose]

Question 6

what happens in type 1 diabetes regarding insulin

Answer 6

beta cell function declines so insulin is not secreted so once injected the liver receives a signal and various body cells to uptake glucose from blood

Question 7

how does body respond to insulin in type 2 diabetes

Answer 7

insulin is produced but the body is overpowered by high glucose level so stops working and no-longer respond to insulin pancreas cant keep up [beta cells] and stop making insulin