Question

During the overall process of protein synthesis, amino acids become covalently attached to

• A. Messenger RNA
• B. Ribosomal RNA
• C. Transfer RNA
• D. More than one of the above

Answer 1

The correct option is C Transfer RNA

In transcription the specific nucleotide sequence of an mRNA specifies which amino acids are incorporated into the protein product of the gene from which the mRNA is transcribed, and the role of tRNA is to specify which sequence from the genetic code corresponds to which amino acid. One end of the tRNA matches the genetic code in a three-nucleotide sequence called the anticodon. The anticodon forms three base pairs with a codon in mRNA during protein biosynthesis. The mRNA encodes a protein as a series of contiguous codons, each of which is recognized by a particular tRNA. On the other end of the tRNA is a covalent attachment to the amino acid that corresponds to the anticodon sequence. Each type of tRNA molecule can be attached to only one type of amino acid, so each organism has many types of tRNA (in fact, because the genetic code contains multiple codons that specify the same amino acid, there are several tRNA molecules bearing different anticodons which also carry the same amino acid).