Final answer:
The process of blood glucose rising after a meal and then returning to baseline is an example of a negative feedback loop, where insulin is released to lower glucose levels back to normal.
Step-by-step explanation:
After a meal, blood glucose levels rise and in response, the body releases insulin to lower the blood glucose back to its baseline. This process is an example of a negative feedback loop, which acts to reverse the direction of the stimulus (in this case, the increased blood glucose levels). This contrasts with a positive feedback loop, which enhances or amplifies the initial stimulus. For instance, blood clotting is an example of a positive feedback loop.
According to the information provided, blood sugar levels are indeed controlled by a negative feedback mechanism. When blood glucose levels rise, insulin is released which facilitates the uptake of glucose by cells, and in the liver, glucose is converted to glycogen, reducing blood sugar levels back to normal.