* mRNA (messenger RNA): This molecule carries the genetic code from DNA in the nucleus to the ribosomes in the cytoplasm. It contains the instructions for building a specific protein.
* tRNA (transfer RNA): These molecules act as "translators" by recognizing specific codons (three-nucleotide sequences) on mRNA and bringing the corresponding amino acid to the ribosome.
The Process of Translation:
1. Initiation: The ribosome attaches to the mRNA and finds the start codon (AUG). The first tRNA carrying the amino acid methionine binds to the start codon.
2. Elongation:
* The ribosome moves along the mRNA, reading each codon.
* For each codon, a specific tRNA molecule with its corresponding amino acid binds to the ribosome.
* The amino acids are linked together by peptide bonds, forming a polypeptide chain.
3. Termination: The ribosome reaches a stop codon on the mRNA. No tRNA recognizes a stop codon, so the ribosome detaches from the mRNA, releasing the completed polypeptide chain.
In summary: mRNA provides the blueprint for the protein, while tRNA delivers the building blocks (amino acids) to construct the protein according to the blueprint. This collaborative process ensures the accurate translation of genetic information into functional proteins.
