- The main biological role of ribosomes within a cell is protein synthesis.
- Ribosomes are complex molecular machines found in all living cells that serve as the site where genetic information encoded in messenger RNA (mRNA) is translated into proteins.
- During this process, ribosomes facilitate the assembly of amino acids into polypeptide chains according to the sequence specified by the mRNA.

- It is important to note that ribosomes do not participate in lipid synthesis, carbohydrate metabolism, or DNA replication, which are functions carried out by other cellular organelles or enzymes.
- For example, lipid synthesis primarily occurs in the smooth endoplasmic reticulum, carbohydrate metabolism involves enzymes in the cytoplasm and mitochondria, and DNA replication takes place in the nucleus.

Therefore, ribosomes are essential for translating genetic information into functional proteins, which are crucial for virtually all cellular processes.

Reference: Molecular Biology of the Cell, 6th Edition, Chapter 6: Protein Synthesis