True, major events like a super volcano's or asteroid strikes can send tons of ash dust and debris into the stratosphere and cause global cooling. <span />
Explanation:
Genetic evolution is the meaning of biologic life, in that it is the why and how of it, as well as the stock of future biological existence. The genes that survive -- and in turn the organisms they make -- are the winners in the existence game. ... We owe our existence to this process, and our future depends on it.
<span>When an athlete is nearing the end of a race and her cells are low on oxygen, it is likely to be fermentation. When cells have used up all their oxygen they ferment glucose into lactic acid. Fermentation is a metabolic process that consumes sugar in the absence of oxygen</span>
