What is the primary function of ribosomes in a cell?

Ribosomes play a crucial role in the cellular process of protein synthesis. They are the molecular machines that translate messenger RNA (mRNA) into polypeptide chains, ultimately folding into functional proteins. This process, known as translation, takes place on ribosomes, which can be found free-floating in the cytoplasm or attached to the endoplasmic reticulum, forming rough ER.

During translation, ribosomes read the sequence of codons on mRNA and help assemble the corresponding amino acids in the correct order, facilitated by transfer RNA (tRNA) that carries the specific amino acids. This synthesis of proteins is vital for cellular function, as proteins are responsible for a diverse range of tasks including structural support, enzymatic activities, and signaling within and between cells. Thus, the primary function of ribosomes is effectively encompassed in their role in protein synthesis.