7th Grade Science Final Exam Study Guide
what is: natural selection?
when one animal isn’t fit to survive in the wild so it doesn’t reproduce and it dies, sometimes the entire species doesn’t survive
what is: over population
when there are to many of one species in one area and they use up all the local resoruces and die out
what is: how is relative age determined
It pretty much staits that the lower something is, then the older it is. and that the higher something is then the younger it is.
what is: a fuel cell
a cell producing an electric current directly from a chemical reaction.
what is: a pollutant
a something that pollutes something, especially water or the atmosphere.
what is: a nonrenewable resource?
it cant be reused, and it is a huge pollutant. Ex. coal, petroleum, natural gas