The answer is = a stimulant
The Arctic Fox lives in the Arctic Tundra (more or less around Alaska, Iceland I think, and other places like that). During the winter, their fur is very thick and solid white (not always SOLID but generally speaking). During the summer and spring, their fur turns brown.
1. Of course, during the winter in those regions, it's going to be snowing and ice is going to be all over the ground. By having a white coat, they're able to blend in and hide from predators, such as the Arctic Wolf and Polar Bears. By turning brown, they'll be able to blend in with the dirt after the snow and ice melts, and again, hide from predators. For the other fox, their brown coat blends in with the dirt, trees, dead leaves, etc. and they'll be able to hide from prey and predators alike.
2. The Arctic Fox also has very thick fur during the winter, which allows it to survive the extreme temperatures. They also dig burrows in the snow for shelter in blizzards. This gives them the ability to survive natural disasters (at least one of them).
I can't think of a third one but these should give you a pretty good idea of how their adaptations help them survive. I really love the Arctic fox so I know quite a bit about them. I really hope this helps you.
Answer:
Repolarization
Explanation:
Repolarization refers to the phase during which the resting potential is restored after depolarization. This means that the inside of the axon membrane becomes negative again compared to the outside.
Repolarization is obtained by the functioning of K+ ion channels. The opening of K+ ion channels allows the K+ to move outside of the axon. Movement of positively charged ion (K+) outside of axon makes the inside negative again and the resting potential is restored.