Scientists are always thinking about ways to improve experimental design. In the text's potato chip experiment, which of these changes would produce the most effective design?
A. Show a different movie.
B. Exclude teenagers as group members.
C. Collect uneaten chip remains and weigh them for both groups.
D. Provide free drinks before the experiment.
E. Use a smaller theater.
Answer: C
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The human chromosomes that do not determine whether an individual is male or female are
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"Self" markers in human cells
A) are lipopolysaccharides of the GALT. B) are glycoproteins of the MHC. C) are identical between individuals. D) are clonally selected.