A prokaryotic ribosome is a cellular structure found in prokaryotic organisms, such as bacteria and archaea. It is responsible for protein synthesis, translating messenger RNA (mRNA) into proteins. Prokaryotic ribosomes are smaller than eukaryotic ribosomes, typically composed of a 70S unit, which includes a 50S large subunit and a 30S small subunit. These ribosomes play a crucial role in the cell's function, as proteins are essential for various biological processes. The structure of prokaryotic ribosomes allows them to efficiently bind to mRNA and tRNA, facilitating the assembly of amino acids into polypeptide chains, which ultimately form proteins.