What is translation, and how do ribosomes and tRNA function in this process?

Translation is the process by which genetic information encoded in mRNA is converted into a sequence of amino acids to form a protein. Ribosomes and tRNA play crucial roles in this process.

Ribosomes are complex molecular machines composed of RNA and proteins. They are responsible for reading the genetic code on mRNA and catalysing the formation of peptide bonds between adjacent amino acids. Ribosomes consist of two subunits, each of which contains a binding site for mRNA and three binding sites for tRNA.

tRNA, or transfer RNA, is a type of RNA molecule that carries amino acids to the ribosome during translation. Each tRNA molecule has a specific anticodon sequence that is complementary to a codon on the mRNA. When a tRNA molecule with the appropriate anticodon binds to the mRNA, the ribosome catalyses the formation of a peptide bond between the amino acid carried by the tRNA and the growing polypeptide chain.

During translation, the ribosome moves along the mRNA in a 5' to 3' direction, reading each codon and recruiting the appropriate tRNA molecule to add the corresponding amino acid to the growing polypeptide chain. This process continues until a stop codon is reached, at which point the ribosome releases the completed protein.

In summary, ribosomes and tRNA work together to translate the genetic code on mRNA into a sequence of amino acids to form a protein. Ribosomes read the mRNA and catalyse peptide bond formation, while tRNA carries amino acids to the ribosome and ensures that the correct amino acid is added to the growing polypeptide chain.