EVOLUTION
THE ORIGIN OF LIFE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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SomeRNA molecules are important catalysts in modern cells.
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The oldest known fossils contain traceamounts of RNA.
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Single-stranded RNA molecules arelinear and do not form three-dimensional shapes.
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RNA is the primary genetic material ofmany viruses.
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Detailed explanation-1: -Hence life on earth began with simple RNA molecule. It further states that life evolved to use DNA and proteins due to the relative instability of RNA and poorer catalytic properties. Thus the correct answer is option d.
Detailed explanation-2: -The unique potential of RNA molecules to act both as information carrier and as catalyst forms the basis of the RNA world hypothesis. RNA therefore has all the properties required of a molecule that could catalyze its own synthesis (Figure 6-92).
Detailed explanation-3: -The RNA world hypothesis suggests that life on Earth began with a simple RNA molecule that could copy itself. The RNA world hypothesis suggests that life on Earth began with a simple RNA molecule that could copy itself without help from other molecules. DNA, RNA, and proteins are central to life on Earth.
Detailed explanation-4: -So, Most biologists think that RNA was the first genetic material because, the existence of ribozymes suggests that early cells could have used RNA to catalyze chemical reactions and transfer information.
Detailed explanation-5: -Thirty years ago, molecular biologist Walter Gilbert published his RNA world hypothesis, which posited that early in evolution living systems were composed entirely of RNA.