If the endoplasmic reticulum were removed from the cell, which organelle would not be able to function properly, and why?

The endoplasmic reticulum helps make and transport proteins and lipids to the Golgi apparatus. The Golgi modifies, sorts, and packages many of these materials, so without the ER it would not receive them normally and could not function properly. Therefore, the correct choice is the Golgi apparatus, because it packages proteins received from the ER.

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