Ribosomes play a key role in protein synthesis — they are the cell’s “protein factories.”
Their main job is to read the genetic instructions carried by messenger RNA (mRNA) and use them to build proteins from amino acids.
Here’s how it works, step by step:
- mRNA binds to the ribosome
After a gene is transcribed into mRNA in the nucleus, the mRNA travels to the cytoplasm and attaches to a ribosome. - tRNA brings amino acids
Transfer RNA (tRNA) molecules carry specific amino acids to the ribosome. Each tRNA matches a set of three bases on the mRNA (called a codon) through its own three-base sequence (called an anticodon). - Ribosome joins amino acids
The ribosome moves along the mRNA, reading the codons one by one. For each codon, it helps link the correct amino acid to the growing protein chain using a peptide bond. - Protein chain grows
The ribosome continues reading the mRNA and adding amino acids until it reaches a stop codon, which signals the end of the protein. - Protein is released
Once complete, the new protein folds into its proper shape and becomes functional.
In short, ribosomes translate genetic information into proteins by connecting amino acids in the correct order. Without ribosomes, cells could not make enzymes, hormones, or structural proteins needed for life.