What defines whether or not organisms belong to the same species?

How have high taxes on tobacco products impacted the number of people who use them? a. the number of tobacco users has increased. b. the number of tobacco users has decreased. c. the number of tobacco users has not changed. d. the number of adolescent tobacco users decreased, while the number of adult users increased

In what cells is the human genome located?

Has anyone taken the genetics unit test in connexus? not looking for answers, just a little bit what to expect and some with studying.