A mutation causes extensive loss of the endoplasmic-reticulum network throughout a eukaryotic cell, while the mitochondr
ER contributes to intracellular transport and to the synthesis of proteins, lipoproteins and glycogen. Rough ER is associated with protein synthesis and secretion, while smooth ER synthesises lipids and lipid-like steroidal hormones.
Ref: NCERT Class 11 Biology Chapter 8: Cell: The Unit of Life Endomembrane System - ER Golgi Lysosome Vacuole
