Answer:
HIV (human immunodeficiency virus) is a virus that attacks a type of white blood cell called a T-helper cell (also called a CD4 cell). People who have been infected with HIV develop AIDS. People with AIDS often develop diseases caused by organisms that usually do not harm people who are not infected with HIV. Explain why the organisms are more harmful to people with HIV than to people without HIV
If the beavers need large teeth to collect wood for their dams, the population of beavers with larger teeth will live longer because they can collect wood. They will them be able to reproduce therefore passing down the gene with larger incisor teeth
To my knowledge, the answer is B
In the lungs, carbon dioxide passes into the air from the blood.
The kings are part of the respiratory system