What is the cancer causing sgent in tobacco?

How does natural selection change thephenotypes within a population over time?

Astudent sees several ants walking up a wall following the exact same trail that an ant took earlier. she wants to apply the scientific method to determine how the ants detected the trail. which of these steps would come first in her application of the scientific method? perform an experiment by cleaning the scent away from part of the trail. draw a conclusion that the ants follow a scent trail. make a prediction about what the ants will do after she cleans away part of the trail. hypothesize that the ants are following a scent trail that the first ant left.

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?