BIOLOGY
STRUCTURE OF NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the four nucleic acid bases combine in three letter sequences that each define an amino acid
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the four nucleic acid bases combine in two letter sequences that each define an amino acid
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the four nucleic acid bases are converted into tRNA molecules which can each attach to sixteen different amino acids
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the four bases each specify one amino acid, and these then combine to form the other sixteen amino acids
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Detailed explanation-1: -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). The adaptor molecule for translation is tRNA.
Detailed explanation-2: -How do the four different nucleotides found in DNA result in twenty different amino acids that are then used to form proteins in the cell? The four nucleic acid bases combine in 3 letter sequences to make an amino acid.
Detailed explanation-3: -Each amino acid is represented by a sequence of three DNA bases, called a triplet. Because 4 different bases can be combined into 64 different triplets, most of the 20 amino acids are represented by more than 1 triplet.
Detailed explanation-4: -Genetic Code: The sequence of nucleotides, coded in triplets (codons) along the mRNA, that determines the sequence of amino acids in protein synthesis. A gene’s DNA sequence can be used to predict the mRNA sequence, and the genetic code can in turn be used to predict the amino acid sequence.
Detailed explanation-5: -11. How can only four bases in RNA carry instructions for 20 different amino acids? The genetic code is read three letters at a time, so that each “word” of the coded message is three bases long. that is to be added to a polypeptide.