Small things to correct

Question 1

What is the difference between endocrine and exocrine?

Answer 1

Endocrine - secrete hormones Directly into the blood
Exocrine - Secretes substances via ducts

Question 2

What are the different types of stem cell and what can they differentiate into?

Answer 2

-Totipotent - ANY cell type
-Multipotent - Any type of blood cell
-Pluripoteint - any cell type except unbillical / placenta cells

Question 3

How is insulin secreted by Beta Cells?

Answer 3

Beta cells have both K+ and Ca2+ channels, K+ channels are normally open allowing K+ to leave the cell.
When there is a high glucose concentration, glucose diffuses into the cell and is metabolised to produce ATP.
ATP blocks the K+ channels causing the inside of the cell to become less negative.
This causes Ca2+ channels tp open so calcium flows into the cell
Ca2+ causes vesicles containing insulin to move to and fuse with the cell membrane so insulin is released by exocytosis.