How many pairs of chromosomes are in each cell of the human body?

You volunteer to participate in a research experiment. You participate in a variety of test procedures and interviews. Later, however, you learn that another group of participants had an experimental treatment that you and members of your group did not have. This is because you

a. were disqualified. c. were in the control group. b. failed earlier tests. d. were in the treatment group.

Which of the following occurs during the excitement phase?

a. the clitoris shortens c. thinning of the scrotal skin b. breasts enlarge d. testes become lowered