Question

Where does the glycosylation of protein occur?
A. Endoplasmic reticulum
B. Lysosomes
C. Mitochondria
D. Chloroplast

Answer 1

Glycosylation is the attachment of sugar molecules to proteins by glycosidic linkage. Besides, the process happens within the cell organelle in which the synthesis of proteins and lipids takes place. The glycosyl donor here is attached to hydroxyl.

Complete step by step answer: Electron microscopic studies of eukaryotic cells reveal the presence of a network or reticulum of little hollow structures scattered within the living substance that's known as the endoplasmic reticulum (ER). The addition of a saccharide moiety to a molecule is noted as supermolecule glycosylation. Glycosylation is the attachment of sugar molecules to proteins by glycosidic linkage. It takes place within the ER (Endoplasmic Reticulum) and the Golgi complex body of the cell. Hence glycosylation of supermolecules happens in the Endoplasmic reticulum.
-The lysosomes present in the cell are responsible for the digestion of macromolecules. They are also responsible for cell repairs.
-Mitochondria in cells are known as the powerhouse of the cell. It is the site of ATP synthesis.
-The chloroplast is present in plant cells. It converts sunlight into chemical energy, so it absorbs sunlight. Thus, it is a major component of photosynthesis.
Hence, the correct answer is Endoplasmic reticulum, i.e., option A.

Note: Glycosylation is that the reaction within which a supermolecule, i.e. a glycosyl donor, is connected to a hydroxyl or different useful group of another molecule. In biology, glycosylation chiefly refers especially to the accelerator(enzyme) method that attaches glycan’s to proteins, or different organic molecules. Also, the Golgi complex or the Golgi apparatus is the center for glycosylation as well as protein trafficking. It is a protein or can be called an enzyme-directed chemical reaction.