Which of the following statements with respect to Endoplasmic Reticulum is incorrect?
- RER has ribosomes attached to ER
- SER is devoid of ribosomes
- Only RER are present in prokaryotes
- SER are the sites for lipid synthesis
Answer
(3) Only RER are present in prokaryotes
Solution
As per NCERT, the endoplasmic reticulum (ER) is a network of membranous tubules found in eukaryotic cells; prokaryotes lack membrane-bound organelles, so neither RER nor SER is present in them.
ER bearing ribosomes on its surface is rough ER (RER); ER without ribosomes is smooth ER (SER), the major site for synthesis of lipids.
The statement 'Only RER are present in prokaryotes' is incorrect.
Answer: (3)