Answers;
To move proteins and other substances through the cell
Step-by-step explanation;
The endoplasmic reticulum is the organelle that moves proteins and other substances through the cell.
The Endoplasmic Reticulum or ER is an extensive system of internal membranes that move proteins and other substances through the cell. The part of the ER with attached ribosomes is called the rough ER.
The rough endoplasmic reticulum helps transport proteins that are made by the attached ribosomes.