Female mosquitoes need a meal of blood from a person or other animal in order to
produce eggs. it has been discovered that mosquitoes have cells on their antennae that can
detect the insect repellent known as deet. the repellent is not harmful to mosquitoes, but
when mosquitoes detect deet, they will not land on the surface where the deet has
been applied. this protects people from being bitten by mosquitoes.
recently, scientists found some mosquitoes that are resistant to deet because they do
not detect its presence. they bred these mosquitoes and eventually produced a population
consisting of about 50% deet-resistant insects.

mosquitoes with deet resistance have been found in natural environments. explain how the continued
use of this repellent may cause the percentage of these resistant mosquitoes to increase in the future.