Why blood glucose changes
The concentration of glucose in the blood changes in response to several factors, including:
- consumption of foods containing carbohydrates;
- exercise;
- secretion of hormones involved in glucose regulation.
| Hormone | Overall effect |
|---|---|
| Insulin | Causes blood glucose concentration to decrease. |
| Glucagon | Causes blood glucose concentration to increase. |
| Adrenaline | Can increase blood glucose concentration. |
These responses contribute to negative feedback, opposing departures in blood glucose concentration and moving it back towards its normal range.
Responses in the pancreas
When glucose concentration becomes too high, pancreatic β cells release insulin. Its effects increase glucose removal from the blood and promote its storage as glycogen.
When glucose concentration becomes too low, pancreatic α cells release glucagon. This activates metabolic processes that increase the amount of glucose available to the blood.
Adrenaline provides another route for increasing blood glucose by activating enzymes involved in glycogen breakdown.