Question

1. what is the stimulus?
2. is this a positive or negative feedback loop?

(the image shows a blood glucose regulation feedback loop with text and images: stimulus (high blood glucose level), high blood glucose level is detected by cells of pancreas, pancreas secretes..., liver cells..., body cells take up blood glucose..., return to homeostasis blood glucose level)

Explanation:

1. The stimulus is the trigger that starts the homeostatic pathway, which in this diagram is the elevated blood glucose level.
2. This is a negative feedback loop because the response (lowering blood glucose) reverses the initial stimulus (high blood glucose) and returns the system to a homeostatic state, rather than amplifying the stimulus.

Answer:

1. The stimulus is high blood glucose level.
2. This is a negative feedback loop.