Muscle cell activity increases and atp decreases below the set-point, a sensor molecule detects low atp and activates protein kinase a, protein kinase a activates protein kinase b, protein kinase b activates transporters that absorb glucose into the cell, glucose is metabolized. this is a:

Negative feedback mechanism

Explanation:

A negative feedback mechanism occurs when there is some change in the homeostatic conditions of the body. These changes are sensed as stimuli and the desired response is generated to oppose the change and to restore the original condition. In the given example, the reduced levels of ATP in muscle cells during increased muscular activity are sensed as a stimulus. The body restores the ATP levels by stimulating the absorption and metabolism of glucose by the cell. Therefore, it represents a negative feedback mechanism.

c. heat from the poles back down towards the equator.