6C: Regulation of blood glucose Flashcards
What are the target cells of insulin?
Skeletal muscle cells
Liver cells
Fat cells
What are the target cells of glucagon?
Skeletal muscle cells
Liver cells
How is ATP formed?
Respiration breaks glucose up into smaller parcels of energy called ATP
Why can’t glucose be stored in the body?
Osmotic effect/soluble
It is instead stored in cells as an insoluble glucose polymer called glycogen.
What is glycogen?
A long series of glucose molecules joined together, and can be stored for prolonged periods of time.
What is glycogenesis?
When glucose molecules join together to form glycogen.
What is glycogenolysis?
When glycogen breaks down into glucose
When can glycogenolysis occur?
When you don’t eat for a while or exercise strenuously and use up available glucose
Why is hyperglycaemia bad?
Glucose can harm the body (damage supply - vessels- to organs)
Why is hypoglycaemia bad?
Not able to supply cells with enough energy for proper function
What is the receptor for regulation of blood glucose?
Islets of Langerhans
What are the effectors and their responses when blood glucose levels are higher than 5 mmol/L?
Skeletal muscle + fat cells -> Increased uptake of glucose via insertion of glucose transports into cell membrane
Liver cells + skeletal muscle cells -> Increased glycogenesis
What are the effectors and their responses when blood glucose levels are lower than 5 mmol/L?
Liver cells + skeletal muscle cells -> glycogenolysis, glucose released into bloodstream
How does insulin work?
Travel in bloodstream to liver and muscle cells, and bind to receptors on cell membrane. Insulin increases permeability, so more glucose is moved from bloodstream to cell.
Also stimulates glycogenesis
What is the normal range of blood glucose levels, and the optimum level?
4.0mmol/L - 7.8mmol/L
Optimum: 5.0mmol/L
