Control of Insulin Secretion

Question 1

What happens during normal blood glucose levels with insulin secretion?

Answer 1

potassium ion channel is open - so potassium diffuses out of the B-cell

inside of cell is relatively negative - calcium ion channel is closed

Question 2

What happens during high blood glucose levels with insulin secretion?

Answer 2

blood glucose levels become high - glucose enters by facilitated diffusion

glucose is respired to form ATP in the mitochondria

ATP blocks the potassium channel - membrane depolarizes - calcium ion channels OPEN - calcium diffuses into B -cells

causes the vesicles of insulin to be released by exocytosis