What is the role of ribosomes in protein synthesis?

What is the role of ribosomes in protein synthesis?

• A. To transcribe DNA into RNA
• B. To synthesize proteins by linking amino acids
• C. To modify mRNA
• D. To transport amino acids

Answer: (B)

Ribosomes play a crucial role in protein synthesis by synthesizing proteins through the process of translation. During this process, ribosomes link amino acids together in the specific order dictated by the sequence of codons on the mRNA (messenger RNA). The ribosome reads the mRNA three nucleotides at a time (each triplet, known as a codon), and for each codon, a corresponding tRNA (transfer RNA) molecule brings the appropriate amino acid to the ribosome. The ribosome then catalyzes the formation of peptide bonds between these amino acids, resulting in a growing polypeptide chain that ultimately folds into a functional protein. The other options refer to different molecular processes that are pivotal in cellular function but do not describe the ribosome's primary role in protein synthesis. Transcribing DNA into RNA is a function of RNA polymerase. Modifying mRNA occurs in the nucleus prior to translation and involves processes such as splicing and the addition of a 5' cap and a poly-A tail. Transporting amino acids is the role of tRNA and other transport proteins, but does not involve ribosomes directly in that function. Thus, the linking of amino acids by ribosomes is what directly constitutes the synthesis of

Ribosomes play a crucial role in protein synthesis by synthesizing proteins through the process of translation. During this process, ribosomes link amino acids together in the specific order dictated by the sequence of codons on the mRNA (messenger RNA). The ribosome reads the mRNA three nucleotides at a time (each triplet, known as a codon), and for each codon, a corresponding tRNA (transfer RNA) molecule brings the appropriate amino acid to the ribosome. The ribosome then catalyzes the formation of peptide bonds between these amino acids, resulting in a growing polypeptide chain that ultimately folds into a functional protein.

The other options refer to different molecular processes that are pivotal in cellular function but do not describe the ribosome's primary role in protein synthesis. Transcribing DNA into RNA is a function of RNA polymerase. Modifying mRNA occurs in the nucleus prior to translation and involves processes such as splicing and the addition of a 5' cap and a poly-A tail. Transporting amino acids is the role of tRNA and other transport proteins, but does not involve ribosomes directly in that function. Thus, the linking of amino acids by ribosomes is what directly constitutes the synthesis of