The 80S ribosomal subunit is a crucial component of the ribosome, which is the cellular machinery responsible for protein synthesis in eukaryotic cells. It is composed of two smaller subunits: the 40S small subunit and the 60S large subunit. Together, these subunits facilitate the translation of messenger RNA (mRNA) into proteins by decoding the genetic information carried by the mRNA. The term "80S" refers to the sedimentation coefficient, a measure of the size and density of the ribosomal particles during centrifugation. This classification distinguishes eukaryotic ribosomes from prokaryotic ribosomes, which are typically classified as 70S. The 80S ribosomal subunit plays a vital role in ensuring accurate and efficient protein synthesis, essential for cellular function and growth.