Creatinine is a toxin produced during the metabolism of meat in our body. Therefore, people with lots of muscles or who eat lots of meat always have a relatively high creatinine level, but it usually fluctuates in the normal range: 0.5-1.3mg/dL.
comet definition An object that enters the inner solar system, typically in a very elongated orbit around the sun. Material is boiled off from the comet by the heat of the sun, so that a characteristic tail is formed.
When far from Sun, they remain frozen. In this state comets are sometimes referred to as _______since about half of their material is ice. Comets are believed to be the oldest, most primitive bodies in the solar system, possibly comprised of some of the basic building blocks of life.