The gene for hemophilia is carried on the sex chromosomes, which makes the disorder an example of a __________ gene.

The disk-shaped structure that nourishes the embryo and fetus is called the:

a. amniotic sac b. umbilical disk c. embryonic disk d. placenta

The term used by the textbook for the study of how our brain and nervous system affect personality and behavior is______________

Fill in the blank(s) with the appropriate word(s).