Ribosomes are cellular organelles responsible for protein synthesis, or the production of proteins. They are found in all living cells, including bacteria, archaea, and eukaryotes.
The function of a ribosome is to translate the genetic information stored in messenger RNA (mRNA) molecules into chains of amino acids, which are the building blocks of proteins. Ribosomes do this by reading the sequence of codons in the mRNA and assembling the corresponding amino acids into a chain, which then folds into a functional protein.
Ribosomes are composed of two subunits, each made up of ribosomal RNA (rRNA) and proteins. They can be found either free-floating in the cytoplasm or attached to the endoplasmic reticulum (ER) in eukaryotic cells. The ribosomes attached to the ER are responsible for producing proteins that will be exported outside of the cell, while the free-floating ribosomes are involved in producing proteins that will be used within the cell.
Overall, ribosomes play a crucial role in the synthesis of proteins, which are essential for many cellular processes, including cell growth, repair, and metabolism.