The arctic fox has to compete with other predators for its food sources. the main food sources for the arctic fox are rabbits and other small rodents. what would happen if competition for food in the arctic increased and it was difficult for the arctic fox to find its prey?

The Arctic fox would either go extinct or it would adapt to seek out new sources of food. These could be the chicks of seabird colonies or walrus/seal pups. It could also adapt to feed on the young of its competitors. Another feeding adaptation would be to scavenge for dead animals or the kills of other predators. Thess adaptions might require behavioural and/or physical changes to be evolved. 

Leaves specifically the gas exchange between plants and the environment. while plants undergo photosynthesis, they also partake in cellular respiration. respiration is the process that happens in the leaves of plants.