4. A disease resistance gene is a gene that either lessens the
symptoms of a disease or helps
an organism avoid getting the
disease in the first place. Explain
why the mutation to the CCR5
gene results in an allele that
provides disease resistance.

the answer is

c. parental

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation: