Flashcards in Hormones & the regulation of blood glucose concentration Deck (9):
What are hormones?
-secreted form glands into the blood
-carried by the blood plasma to target cells
-widespread, long lasting effects
What is the second messenger model?
-hormones activate chemical pathways in calls by binding to receptors on the cells to create a second messenger chemical to be produced in cells by activating an enzyme in the cell by changing its tertiary structure
-for example adrenaline causes ATP to produce cAMP which activates an enzyme which converts glycogen to glucose
What is the role of the pancreas in regulating blood glucose?
-it produces enzymes for digestion and the hormones insulin and glycogen from the islets of Langerhans
What are the cells of the islets of Langerhans?
-alpha cells = larger, produce glucagon when there is a low concentration of glucose as glucagon converts glucose to glycogen and forms glucose from glycogen
-beta cells = smaller, produce insulin when the blood glucose level is high as it opens chemical pathways for glucose to be stored as glycogen and fat, it also increases the respiratory rate
Which sources do blood glucose come from?
- hydrolysis of food
What is blood glucose?
-eating increases blood glucose
-exercise decreases blood glucose
What does adrenaline do?
-produces glucose for the fight or flight response
-produces by adrenal glands above the kidneys
-breaks down glycogen
What is the feedback mechanism?
-glucagon increases glucose levels
-insulin decreases glucose levels which prevents it ever getting too high or too low