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.
Ground Squirrel â Five or more species of ground squirrel live in Texas, mostly in the western part of the state. The rock squirrel (Spermophilus variegatus) is found throughout the Edwards Plateau and Trans-Pecos. The Mexican ground squirrel (Spermophilus mexicanus) is found in southern and western Texas.