At the end of high school, about 65 percent of U.S. young people have had sexual intercourse; by age 25, __________ have done so

For James, what best describes the role that biology, psychophysics, experimental psychology, archeology, religion, mysticism, and parapsychology played in psychology?

a. They formed the basis for his Jamesian psychology. b. They were irrelevant in light of the development of the experimental laboratory. c. They informed his understanding and development of psychological theory. d. They were avid personal, but not professional, interests.

When both of the alleles for a trait, such as hair color, are the same, the person is said to be _____ for that trait

A) monozygotic B) dizygotic C) homozygous D) hemizygous