The organelle responsible for protein synthesis in cells is the ribosome. Ribosomes can either be found freely floating in the cytoplasm or attached to the endoplasmic reticulum, specifically the rough ER. They read the genetic information encoded in messenger RNA (mRNA) and use transfer RNA (tRNA) to assemble amino acids into polypeptide chains, ultimately folding into functional proteins. This process is essential for cellular function and growth as proteins carry out many cellular roles including structural support, enzymatic activities, and signaling.