THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Detailed explanation-1: -With three bases, there are 43 = 64 codons, which is more than enough to encode the 20 amino acids. Therefore, the genetic code is degenerate, which means more than one triplet can encode the same amino acid. Each amino acid can have more than one codon, but no codon can encode more than one amino acid.
Detailed explanation-2: -The code: codons. In a DNA sequence, the code for each of the 20 naturally-occurring amino acids consists of a sequence of three nucleotide bases, which we’ll just refer to with three “letters, ” like ATG, or CCC. Recall that A = adenine, C = cytosine, T = thymine (or U = uracil in RNA), and G = guanine.
Detailed explanation-3: -Three is the minimum number of nucleotides per codon needed to encode 20 amino acids.
Detailed explanation-4: -Each codon represents a single amino acid. Therefore, nine nucleotide bases are required to code for three amino acids. Note: A genetic code chart represents different combinations of the four nucleotide bases.
Detailed explanation-5: -Because there are only 20 different amino acids but 64 possible codons, most amino acids are indicated by more than one codon. (Note, however, that each codon represents only one amino acid or stop codon.)