Insulin Secretion

Question 1

1.

Answer 1

When blood glucose concentration increases, it’s detected by B cells in the Islets of Langerhan.

Question 2

2.

Answer 2

K+ channels open and K+ diffuse out making inside of membrane more negative (-60mV).

Question 3

3.

Answer 3

Glucose diffuses into B cells where its metabolised to form ATP.

Question 4

4.

Answer 4

High levels of ATP cause K+ channels to close so K+ can’t diffuse out and membrane potential becomes less negative (-30mV).

Question 5

5.

Answer 5

This causes Ca2+ channels to open and Ca2+ diffuse into cell, causing vesicles to move and fuse to membrane, releasing insulin via exocytosis.