The width of a DNA double helix ____
a. is constant
b. is narrower where adenine is present than where cytosine is present
c. is wider where purines are present than where pyrimidines are present
d. varies randomly
e. is wider where pyrimidines are present than where purines are present
ANSWER: a
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In the section "Investigating Life: Birds Do, Bees Do It", what hypothesis did the researchers test?
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