insulin secretion

Question 1

where is insulin secreted from?

Answer 1

beta cells of islets of langerhans in the pancreas

Question 2

what do alpha cells produce

Answer 2

glucagon

Question 3

What initial step triggers insulin secretion

Answer 3

Blood glucose concentration is high, so more glucose enters a beta cells by facilitated diffusion

Question 4

what happens when glucose enters the cell

Answer 4

More glucose in beta cells, causes the respiration to increase making more ATP

Question 5

what did an increase in ATP cause

Answer 5

atp sensitive potassium(K+)channels close

Question 6

what does the closure of k+ channels cause?

Answer 6

This means potassium ions can’t get through the membranes they build up inside the cell, Causing The plasma membrane to depolarise

Question 7

depolarisation definition

Answer 7

The inside of the beta cell is less negative because there are more positively charged potassium ions inside the cell

Question 8

what does depolarisation lead to

Answer 8

ca+ion channels open

Question 9

what does the opening of the ca+ channel ions result in

Answer 9

influx of ca+ ions inside the cell

Question 10

what doe a ca+ influx cause

Answer 10

signals insulin filled vesicle to merge with membrane(exocytosis) secretion of insulin