本题目来源于试卷: Unity and Diversity A.3 Origin of Cells，类别为 IB生物学
[单选题]
Which of the following statements are reasons that78raac2es q 85guul7k RNA is*-e. b8xvag jt believed to be the first genetic materia. g-*ta8xbvj el?
I. RNA can form spontaneously when nucleotides are present
II. RNA contains ribose as its sugar
III. Miller demonstrated that organic molecules could be produced from a mixture of gases under conditions that simulated early Earth
A. I only
B. I and III
C. II and III
D. I, II and III
参考答案: B
本题详细解析:
RNA is believed to be a potential can l5dlo n9( qu/b24lzf va,c,qhdidate for the first genetic material due to its ability to form spontaneously from nucleotides (Statement I). Miller's famous experiment demonstrated that simple organic molecules, including nucleotides, could be produced from a mixture of gases under conditions that simulated early Earth (Statement III). This experiment suggested that nucleotides could have formed spontaneously on a prebiotic Earth, providing hd a5o fn,ul9l(/ vl2qcz, 4bqa plausible scenario for the emergence of RNA as the first genetic material. Therefore Choice B is correct.
Choice A only included Statement I and not II, so it is incorrect. While it is true that RNA contains ribose as its sugar component (Statement II), the presence of ribose is not a primary reason for RNA being considered the first genetic material. Both RNA and DNA contain sugars in their structures, but the key point in favour of RNA as the first genetic material is its ability to form spontaneously. Choices C and D included Statement II and so are incorrect.
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