Which organelle is primarily involved in synthesizing proteins?

The correct answer is ribosomes. Ribosomes are the cellular machines responsible for translating messenger RNA (mRNA) into proteins. They facilitate the assembly of amino acids in the order specified by the mRNA, which dictates the sequence of the polypeptide chain, ultimately forming proteins. Ribosomes can be found freely floating in the cytoplasm or attached to the endoplasmic reticulum, which is known as rough ER when ribosomes are present. This structural relationship enhances the efficiency of protein synthesis.

Understanding the role of ribosomes is essential because they are critical for the function and maintenance of all cells, as proteins serve a multitude of roles, including serving as enzymes, structural components, signaling molecules, and more. This specificity in function underscores the importance of ribosomes in the overall biology of the cell.