22. The most significant feature of bulimia nervosa is ____________.
(A) purging
(B) overeating
(C) overeating followed by an urge to vomit
(D) binge eating followed by compensatory behavior

18. Persistent depressive disorder (PDD) differs from major depressive disorder because people diagnosed with PDD have symptoms of depression that are ________. (A) longer-lasting (B) temporary (C) more severe (D) episodic

19. The rapid-cycling specifier refers to an individual with bipolar disorder who experiences at least ___ manic or depressive episodes in a year. (A) 2 (B) 4 (C) 6 (D) 8

20. Current research into neurotransmitter systems has produced the "permissive" hypothesis, which states that (A) low levels of serotonin are sufficient to explain the etiology of mood disorders. (B) the norepinephrine system regulates serotonin levels； if norepinephrine is low, depression will occur. (C) when serotonin levels are low, other neurotransmitter systems become dysregulated and contribute to mood irregularities. (D) the absolute levels of neurotransmitters are more significant in mood regulation than the overall balance of the various neurotransmitters.

21. Which of the following statements is TRUE about tricyclics? (A) Tricyclics work within 24 hours after they are ingested. (B) Weight loss is a side effect of taking a tricyclic. (C) Tricyclics block the reuptake of acetylcholine. (D) They can be accompanied by very unpleasant side effects.

23. Research using brain-imaging techniques has localized auditory hallucinations in the part of the brain called _____________. (A) Wernicke's area (B) Broca's area (C) the occipital lobe (D) the limbic system

24. The negative schizophrenic symptom called avolition is defined as (A) inability to initiate and persist in activities. (B) inability to experience pleasure. (C) lack of emotional response, blank facial expression. (D) lack of speech content and/or slowed speech response.

25. Tardive dyskinesia, a condition that can occur in patients who take antipsychotic medications, (A) can result from short-term use. (B) can result from low doses. (C) occurs in less than 2% of patients. (D) may often be irreversible.

1. A student performs an experiment to determine the density of a sugar solution. She obtains the following results: 4.71 g/mL, 4.73 g/mL, 4.67 g/mL, 4.69 g/mL. If the actual value for the density of the sugar solution is 4.40 g/mL, which statement below best describes her results? (A) Her results are precise, but not accurate. (B) Her results are accurate, but not precise. (C) Her results are both precise and accurate. (D) Her results are neither precise nor accurate.

2. What answer should be reported, with the correct number of significant figures, for the following calculation? (249.362 + 41) / 63.498 (A) 4.6 (B) 4.57 (C) 4.573 (D) 4.5728

3. Write the name for Ca3(PO4)2. (A) calcium (III) phosphite (B) calcium (II) phosphite (C) calcium phosphate (D) tricalcium phosphorustetraoxide