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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single base pair in RNA
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single Amino Acid
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entire protein
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single base pair in DNA
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Detailed explanation-1: -In 9 groups of codons, the nucleotides at the first two positions are sufficient to specify a unique amino acid, and any nucleotide (abbreviated N) at the third position encodes that same amino acid.
Detailed explanation-2: -A codon consists of three consecutive nucleotides on mRNA that specify a particular amino acid.
Detailed explanation-3: -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.)
Detailed explanation-4: -mRNA codons are read from 5’ to 3’, and they specify the order of amino acids in a protein from N-terminus (methionine) to C-terminus. Translation involves reading the mRNA nucleotides in groups of three; each group specifies an amino acid (or provides a stop signal indicating that translation is finished).
Detailed explanation-5: -As such, a genetic code is a triplet code in which a sequence of three bases is needed to specify one amino acid. The genetic code translates the RNA sequences into the amino acid sequence (Fig. 4.17). Each group of three ribonucleotides, called a codon, specifies one amino acid.