BIOLOGY
STRUCTURE OF PROTEINS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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4
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2
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6
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12
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Detailed explanation-1: -A start codon is made up of the letters ATG, which codes for the amino acid methionine.
Detailed explanation-2: -Each group of three nucleotides encodes one amino acid. Since there are 64 combinations of 4 nucleotides taken three at a time and only 20 amino acids, the code is degenerate (more than one codon per amino acid, in most cases).
Detailed explanation-3: -This leads to a total of 10 codons in the mRNA sequence AUGGCAGUGCCA as AUG, UGG, GGC, GCA, CAG, AGU, GUG, UGC, GCC, CCA.
Detailed explanation-4: -It had long been known that only 20 amino acids occur in naturally derived proteins. It was also known that there are only four nucleotides in mRNA: adenine (A), uracil (U), guanine (G), and cytosine (C). Thus, 20 amino acids are coded by only four unique bases in mRNA, but just how is this coding achieved?