5.3.2: Control of blood glucose concentration
Not started yet — this one needs some love.
Blood glucose concentration is monitored and controlled by the pancreas.
If blood glucose is too high, the pancreas produces insulin.
Insulin causes glucose to move from the blood into cells.
In liver and muscle cells, excess glucose is converted to glycogen for storage.
Type 1 diabetes occurs when the pancreas fails to produce sufficient insulin, causing uncontrolled high blood glucose.
Type 1 diabetes is normally treated with insulin injections.
Type 2 diabetes occurs when body cells no longer respond to insulin produced by the pancreas.
Type 2 diabetes is commonly treated with a carbohydrate-controlled diet and exercise; obesity is a risk factor.
Higher tier: if blood glucose is too low, the pancreas produces glucagon, which causes glycogen to be converted into glucose and released into the blood.
Insulin and glucagon interact in a negative feedback cycle to control blood glucose levels.
Common exam mistakes
Do not confuse insulin and glucagon: insulin lowers blood glucose, while glucagon raises it.
Do not choose a graph time when blood glucose is low if the question asks when insulin would be high.
Insulin causes glucose to move into cells; answers that only say glucose is taken out of the blood are incomplete.
Type 1 diabetes is normally treated with insulin injections, not diet alone.
When comparing diabetes data, compare values directly; quoting two numbers without saying which is higher is not enough.