EVOLUTION
THE ORIGIN OF LIFE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Many of the most critical elements of cells are composed mostly or entirely of RNA.
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RNA has been demonstrated to act as a catalyst in modern cells.
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Modern cells use an RNA template when synthesizing proteins.
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In modern cells, RNA provides the template on which DNA nucleotides are assembled.
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Detailed explanation-1: -The RNA world hypothesis is supported by RNA’s ability both to store, transmit, and duplicate genetic information, as DNA does, and to perform enzymatic reactions, like protein-based enzymes.
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: -RNA is the first genetic material in cells because: RNA is capable of both storing genetic information and catalyzing chemical reactions. Essential life processes like metabolism, translation, splicing, etc. evolved around RNA.
Detailed explanation-4: -The main evidence supporting this hypothesis is the discovery that RNA can act as both a store of genetic information and as a cellular catalyst. The hypothesis is also supported by the fact that RNA can effectively self-replicate.