Question

Which is/are not the correct function(s) of endoplasmic reticulum?

I. RER is involved in the protein synthesis, and responsible for post-translational modifications of the polypeptide chain.

II. RER is involved in synthesis of glycoproteins and glycolipids.

III. SER of liver cells is involved in detoxification of toxins and drugs.

IV. SER is also involved in synthesis and storage of lipids including cholesterol and phospholipids.

• A. Only I
• B. Only II
• C. Only II & III
• D. Only III & IV

Answer 1

The correct option is B Only II

I. RER provides a surface for protein synthesis and after the synthesis of the polypeptide chain, it is folded and modified in the lumen of ER which is referred to as post-translational modifications.

II. Golgi bodies are the sites for the synthesis of glycoproteins and glycolipids. It is not the function of RER. Hence option II is incorrect.

III. SER of the liver cells have certain oxygenase enzymes like cytochrome P450, which help in detoxification of toxins and drugs.

IV. SER is directly involved in the synthesis and storage of lipids such as cholesterol and phospholipids.