Multiple choice

Directions: For this question, select the best of the answer choices given.

It is well known that human tears often serve to moisten the eye, protect it from infection, and wash away irritants; such tears are called irritant or reflex tears. Dr. Field hypothesizes that emotional tears have a different biological function. She suggests that by shedding tears when under emotional stress people excrete harmful chemicals that build up in such body fluids as blood serum during emotional stress. Each of the following, if true, provides some support for Dr. Field's hypothesis EXCEPT:

  1. The people most likely to cry when undergoing emotional stress are less likely to suffer from stress-related diseases than is the population at large.

  2. If a local anesthetic is applied to the surface of the eye, irritant and reflex tears are inhibited, but emotional tears are not.

  3. The chemical composition of tears that are induced by grit in the eye is identical to the composition of tears induced by emotional stress.

  4. The concentration of a substance that the body produces only under conditions of emotional stress is thirty times greater in tears than in blood serum.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

C is correct because if emotional tears and irritant tears (from grit) have identical chemical composition, this suggests emotional tears are NOT biologically different or special, which weakens the hypothesis that emotional tears have a unique function of excreting stress chemicals. A supports the hypothesis by showing criers have fewer stress-related diseases. B supports it by showing emotional tears are biologically different from irritant tears. D strongly supports the hypothesis by showing stress-related substances are concentrated in tears at much higher levels than in blood serum, supporting the excretion theory.

Keep practicing — related questions