What is the primary function of ribosomes in protein synthesis?

• A. They break down damaged organelles.
• B. They synthesize proteins.
• C. They store genetic information.
• D. They produce ATP.

Answer: (B)

Ribosomes are the machines that carry out protein synthesis. They read the genetic code carried by messenger RNA and use transfer RNAs to bring in the correct amino acids, linking them together in the order specified by the mRNA to form a polypeptide chain. This translation process builds proteins, functioning whether ribosomes float freely in the cytoplasm or are attached to the rough endoplasmic reticulum. This role is distinct from breaking down damaged organelles, storing genetic information, or producing ATP, which involve other cellular components.