Question

if the endoplasmic reticulum were removed from the cell, which organelle would not be able to function properly, and why?
mitochondria, because they rely on the er as an energy source
ribosomes, because they receive proteins made by the er
golgi apparatus, because it packages proteins received from the er
cytoplasm, because it relies on the er for structural support

Explanation:

The endoplasmic reticulum (ER) is involved in protein synthesis and transport. The Golgi apparatus modifies, sorts, and packages proteins. It receives proteins from the ER. Without the ER, the Golgi apparatus would lack proteins to package. Mitochondria produce energy (ATP) through cellular respiration and do not rely on the ER as an energy source. Ribosomes make proteins, not receive them from the ER. The cytoplasm is a fluid - like substance and does not rely on the ER for structural support in the way described.

Answer:

Golgi apparatus, because it packages proteins received from the ER.