Final answer:
The rough endoplasmic reticulum (RER) gets its name from the ribosomes attached to its cytoplasmic surface, which give it a studded appearance. These ribosomes play a crucial role in protein synthesis and transportation within the cell.
Step-by-step explanation:
The rough endoplasmic reticulum (RER) is named so because the ribosomes attached to its cytoplasmic surface give it a studded appearance. When viewed through an electron microscope, these ribosomes appear as small dots or granules on the surface of the membrane, giving it a rough texture. The RER is responsible for protein synthesis and transportation within the cell.