Question

Which side of the Golgi apparatus has thin membranes?
(a) Concave distal side
(b) Concave proximal side
(c) Convex distal side
(d) Convex proximal side

Answer 1

Hint: Golgi apparatus is a cell organelle found in eukaryotic cells and is majorly engaged in packaging of cellular proteins. It consists of folded and flattened membranes which are filled with cytoplasm. Each membrane has two faces, cis or convex face and trans or concave face. One of the sides is facing the endoplasmic reticulum and the other side is facing the plasma membrane, out of these the side facing the endoplasmic reticulum has thinner membrane than the other.

Complete answer:
The membranes of Golgi apparatus are called cisternae or face. Cis face is also called as convex or forming face. This face receives vesicles containing enzyme or protein from the ER and they have very thin membranes. Trans face is also called a concave or maturing face. This face releases golgi vacuoles which contain modified enzymes or proteins. This face has thicker membranes.

Hence, Convex proximal side of the Golgi apparatus has thin membranes, i.e. option (d) is correct.
Additional Information:Proteins synthesized in the endoplasmic reticulum are packed into vesicles which fuse with Golgi apparatus which are then modified and destined for secretion. Apart from this, Golgi apparatus is also involved in lipid transport and lysosome formation.

Note:The structure and function of Golgi apparatus have close relation. Individual membranes of Golgi apparatus have different assortment of enzymes which allow progressive modification of cargo proteins as they travel from trans face to cis face.