Bipolar disorder is defined as which of the following?

• A. A chronic allergic disorder characterized by episodes of severe breathing difficulty, coughing, and wheezing.
• B. Clouding of the lens
• C. A mood disorder in which the person alternates between the hopelessness and lethargy of depression and the overexcited state of mania.
• D. A malignant growth or tumor caused by abnormal and uncontrolled cell division

Answer: (C)

Bipolar disorder is a mood disorder characterized by episodes of depression and episodes of mania. It involves swings between low, hopeless, low-energy states and highly elevated, energetic states, often with changes in sleep, activity, and thinking. This pattern of alternating mood states is what defines the condition.

The other descriptions point to conditions that are not mood disorders: one describes an asthma-like chronic allergic disorder with breathing difficulty, another describes cataracts that cloud the lens, and another describes cancer caused by uncontrolled cell growth. These do not involve the characteristic mood shifts between depression and mania, so they don’t fit bipolar disorder.