tRNA

Transfer RNA is a small RNA molecule that helps build proteins by carrying amino acids to the ribosome. Each tRNA has an anticodon region that pairs with a complementary codon on mRNA, ensuring the correct amino acid is added to the growing protein chain.

• tRNA acts as an "adapter" between nucleic acids and amino acids. Its anticodon (a set of three bases) matches a codon in mRNA, and the tRNA carries the corresponding amino acid.
• Each type of tRNA is linked to a specific amino acid (for example, tRNA^Phe carries phenylalanine). The enzyme aminoacyl-tRNA synthetase attaches the right amino acid to each tRNA.
• tRNAs have a characteristic cloverleaf-like folded structure. Despite being transcribed from DNA, tRNAs are non-coding RNAs (they are not translated into proteins themselves).

• If a question asks, "Which RNA carries amino acids to the ribosome-" the answer is tRNA. A clue might be mention of an 'anticodon' or an "adapter molecule" for translation.
• An exam may test understanding that tRNA is not translated into protein (it's an RNA that functions as RNA). For instance, a question might ask which RNAs are translated - mRNA is, tRNA is not.
• Be wary of confusing codon vs anticodon. A classic question might give a DNA or mRNA codon and ask for the matching anticodon or amino acid - recognizing that anticodon = tRNA is key.