THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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adenine
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thymine
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cytosine
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guanine
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Detailed explanation-1: -Uracil is present only in RNA, whereas thymine is present only in DNA. Thus, thymine is the nitrogenous base which is not present in RNA.
Detailed explanation-2: -Uracil is one of these bases. However, since mRNA is relatively short-lived and any potential faults don’t result in any lasting damage, RNA employs uracil because the instability doesn’t matter as much for RNA. Thymine is also quickly oxidized. The thymine in the nucleus is shielded from oxygen.
Detailed explanation-3: -RNA doesn’t contain thymine bases, replacing them with uracil bases (U), which pair to adenine1.
Detailed explanation-4: -RNA consists of four nitrogenous bases: adenine, cytosine, uracil, and guanine. Uracil is a pyrimidine that is structurally similar to the thymine, another pyrimidine that is found in DNA. Like thymine, uracil can base-pair with adenine (Figure 2).
Detailed explanation-5: -Uracil is present in RNA but not in DNA.