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.
Over 200 species of squirrels live throughout the world, with many different species residing within the United States. The United States is home to five different types of squirrels; fox, gray, red, flying and ground. Some live in the trees, some live in the ground and others appear to fly. Tree squirrels generally have bushy tails, sharp claws and large ears, while ground squirrels have shorter legs and less bushy fur.