Glucose Concentration Levels Flashcards
Insulin is triggered to release when…
The beta cells in islets of langerhans in the pancreas detects blood glucose concentration is too high
Insulin is released from…
Beta cells of islets of langerhans in the pancreas
What is insulin made of?
It is a protein
Insulins target cells are
Liver and skeletal muscle cells
What happens when insulin arrives at its target cells?
It binds to receptor proteins on the target cells cell membrane
What is triggered when insulin binds to insulin receptors?
Vesicles containing glucose carrier proteins inside the target cell will fuse with the cell surface membrane
And activates certain enzymes in the target cells
When glucose carrier proteins fuse with target cell membranes…
More glucose carrier proteins in the cell membrane causes more facilitated diffusion of glucose into the target cell
Enzymes activated by the insulin receptors will….
Catalyse the conversion of glucose to glycogen
When is glucagon released?
When the alpha cells in islets of Langerhan in the pancreas detects the blood glucose concentration is too low
What releases glucagon?
Alpha cells of the islets of langerhans in the pancreas
What is glucagon made of?
Protein
Target cells of glucagon
Only the liver cells
What does glucagon do to the liver target cells?
Binds to receptors on the liver target cells
Binding glucagon to glucagon receptors means…
Activates enzymes which converts glycogen (storage of glucose) to glucose
And converts glycerol/amino acids to glucose
How does glucose leave the target cell after glucagon uses?
Because glucose carrier proteins are always in target cells so can still leave even without insulin
Where is adrenaline produced?
The adrenal glands
When is adrenaline released?
In fight/flight or excitement situations
Adrenaline target cells
Skeletal muscle cells and liver cells
Glucagon vs adrenaline
Glucagon triggers release of glucose when blood glucose levels are too low
Adrenaline triggers release of glucose during fight or flight so more can be respired for ATP
Adrenaline acts how?
Because it binds to receptors on liver and skeletal muscle cells, activates enzymes to convert glycogen to glucose
Glycogenesis
Making of glycogen from glucose in a condensation reaction
When does glycogenesis occur?
When blood glucose gets too high, so is taken in to liver/skeletal muscle cells and converted to glycogen for storage
Detected by insulin
Glycogenolysis
The hydrolysis of glycogen to glucose
When does glycogenolysis occur?
When blood glucose levels get too low and glucagon and adrenaline triggers the hydrolysis to produce more glucose
