Mammals metabolize ammonia into a molecule called urea: As you can see, this molecule contains two atoms of nitrogen. Although it requires metabolic energy to build, it also is less toxic than ammonia, and it requires less water to flush from the system.Your urine's main nitrogenous waste product is urea.ammals metabolize ammonia into a molecule called urea: As you can see, this molecule contains two atoms of nitrogen. Although it requires metabolic energy to build, it also is less toxic than ammonia, and it requires less water to flush from the system.
Tree squirrels are squirrels that live in trees and ground squirrels, like chipmunks and prairie dogs, are squirrels that live in the ground. As a general rule, tree squirrels have longer life spans than ground squirrels.1.
Red Squirrels feed on the seeds and cones of Pine trees, Fir trees and Spruce trees. The Gray Squirrel. They often live in cities and close to humans -- and eat a wide variety of food from nuts, seeds and fruit to human trash including bread, meat and table scraps. Tree squirrels run fast and jump long distances on tiny branches high up in trees. Ground squirrels dig long tunnels very fast.