Nucleus controls the cell, it tells the cell what to do, similar to a brain. Rough ER or Ribosome ER creates the proteins in the cell. Golgi Apparatus packages macromolecules like lipids and proteins for transport.
The correct term to fill in the blank would be intensity. The intensity of exercise determines whether carbohydrates or fat is the predominant source of energy production. During high-intensity workouts, it is the fat that is used as the source of energy production while low-intensity exercises would only use the carbohydrates present for energy.
The altered protein affected the function of the cell membrane. The cell membrane which contain a bilayer control the movement of substance in and out of the cell and organelles. Due to this it is selective permeable to ion and organic molecules.
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.
