What dual role does the endoplasmic reticulum play in the cell?

The endoplasmic reticulum (ER) serves as a crucial organelle in cells with a dual role that includes protein synthesis and detoxification.

In terms of protein synthesis, the rough endoplasmic reticulum is studded with ribosomes, which are the sites of translation where messenger RNA (mRNA) is converted into polypeptide chains. These newly synthesized proteins can be those destined for secretion, incorporation into the cell membrane, or for use within various organelles.

As for detoxification, the smooth endoplasmic reticulum is involved in the metabolism of various substances, including the detoxification of drugs and toxins. It houses enzymes that modify these compounds, making them more water-soluble and easier to excrete from the body. This detoxifying function is particularly important in liver cells, which are heavily involved in processing various metabolic byproducts.

This dual functionality highlights the versatile roles the endoplasmic reticulum plays in maintaining cellular health and metabolic balance. The other options focus on functions that either do not fully represent the significant roles of the ER or combine processes that are not primarily attributed to this organelle.