Final answer:
Translation consists of three key steps: initiation where a ribosome binds to mRNA, elongation involving tRNAs bringing amino acids as the polypeptide chain grows, and termination signified by a stop codon leading to the release of the completed protein. The tRNA molecules play a significant role in translation by delivering the correct amino acids to the ribosome.
Step-by-step explanation:
Translation is the biological process by which the genetic code carried by an mRNA molecule is decoded to produce a specific sequence of amino acids, thereby forming a protein.
This process takes place within the ribosome in the cell cytoplasm and involves several crucial steps.
- Initiation: The small ribosomal subunit binds to the mRNA at the start codon (AUG) along with an initiator tRNA bearing the amino acid methionine.
- Elongation: tRNA molecules, each carrying a specific amino acid, match their anticodon with the mRNA codons at the A-site of the ribosome. Peptide bonds form between the amino acids, extending the polypeptide chain.
- Termination: The process continues until a stop codon is reached, signaling the addition of amino acids to stop. A release factor binds to the ribosome causing the release of the newly synthesized polypeptide chain.
The structure of a tRNA molecule resembles a cloverleaf with an anticodon at one end and an attachment site for a specific amino acid at the other.
Its role in translation is to deliver amino acids to the ribosome, matching its anticodon to the complementary mRNA codon, ensuring that the correct amino acid is added to the growing polypeptide chain.