Different versions of a gene, like brown or white fur color, are called what?

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment

What will happen if two of the base pairs of the stand of the dna are switched

Transposon can cause mutations in genes at or near the site of transposon insertion. it is possible for these elements to transpose away from their original site, causing a reversion of the mutant phenotype. in some cases, however, even more severe phenotypes appear when these elements excise from this site, due to events at or near the mutant allele. what might be happening to the transposon or the nearby gene to create more severe mutations?