Write a 1-2 page essay explaining the role that biology plays in the development of mood disorders, including one’s genetic vulnerability and the effects of different levels of brain chemicals and transmitter substances; define the term endogenous; and discuss the following psychological explanations for mood disorders: a. the psychoanalytic theory of repressed anger; b. the behavioral theory of learned helplessness; c. the cognitive theory that emphasizes self-defeating thinking patterns; and d. the effects of social and environmental stresses.