All species have a certain amount of genetic diversity within their populations. how is genetic diversity important to the concept of natural selection

Which group of chordates does  notpossess true backbones?                 a.  birds      b.  frogs and toads      c.  lampreys      d.  crocodilians

If a set of instructions that determines all of the charactersitics of an organism is comparedto a book, and a chromosme is compared to chaper in the book, then what might be compared to a paragraph in the book?

Select the true statements about eubacteria. most live as decomposers and heterotrophs. most only thrive in a narrow range of environments. certain eubacteria are responsible for food poisoning. eubacteria thrive in extreme environments.