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.
âº NASA Worldbook: Meteors. âº NASA Worldbook: Comets. âº Wikipedia: Southern Delta Aquariids Summer means fireworks, and here's how to see some of Nature's best displays. Start with a few comets streaking around the solar system, leaving behind dusty trails of gas, ice, rocks and dust.