Studies have found abnormally small lateral ventricles in the brains of schizophrenic people.

The structure that serves as a biological clock and controls human circadian rhythms is the:

A. heart with its pacemaker cells. B. pituitary gland. C. pineal gland. D. suprachiasmatic nucleus.

According to Charles Darwin, emotions are

a. designed to deal with recurring situations in the world. b. most relevant in situations that are novel in a species' experience. c. vague, unpredictable, and personal states of mind. d. likely to vary dramatically from human to human.