Chemicals produced by the body that dull the sensation of pain are called:

A report in a research journal describes the symptoms of a mental disorder along with information on its etiology, including a heritability of 50 percent. How should this finding be interpreted?

a. Genetic factors and the environment contribute about equally to this disorder. b. Half of the people who suffer from the disorder have a genetically caused disorder. c. Half of the children of carriers of this disorder will actually develop the disorder. d. Geneticists have identified half of the genes thought to be responsible for this disorder.

Which of the following doesn't contribute to workplace stress?

a. work overload b. role conflict c. incompetent colleagues d. lack of personal fit with a job e. clear job description