OBJECTIVE LIFE SCIENCE
MOLECULAR BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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pair of nucleic acid and sugar
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pair of phosphate and sugar
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three-base code
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two-base code
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Detailed explanation-1: -Each group of three bases in mRNA constitutes a codon, and each codon specifies a particular amino acid (hence, it is a triplet code). The mRNA sequence is thus used as a template to assemble-in order-the chain of amino acids that form a protein.
Detailed explanation-2: -A codon is the amino acid coding unit in DNA or messenger RNA (mRNA). The string of codons in the mRNA specifies the order of amino acids in the encoded protein. Apart from amino acids, there are also codons that specify start/stop signals.
Detailed explanation-3: -Codons are made up of any triplet combination of the four nitrogenous bases adenine (A), guanine (G), cytosine (C), or uracil (U). Of the 64 possible codon sequences, 61 specify the 20 amino acids that make up proteins and three are stop signals.
Detailed explanation-4: -The three-letter nature of codons means that the four nucleotides found in mRNA-A, U, G, and C-can produce a total of 64 different combinations. Of these 64 codons, 61 represent amino acids, and the remaining three represent stop signals, which trigger the end of protein synthesis.