After being formed by the ribosomes located on the rough endoplasmic reticulum (rough er), what is the next organelle to which a protein could be transported?

To the Golgi apparatus

Explanation:

When a protein is already made by the rough endoplastic reticulum, they need to be transported to the membrane and then to the outside part of the cell to travel trough the blood to the organ that is needed.

So the Golgi apparatus "absorb" the protein and from then, it cover in some lysosomes to transport to the membrane, and then to the outside part of the cell.

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