Question

A membrane protein is made and inserted into the membrane of the rough endoplasmic reticulum. A binding site that is present in this protein is aligned so that it faces the lumen of the ER. If this protein is then moved to other endomembranes, at which surface of the membranes given below is this binding site unlikely to be found? a. the internal face of the Golgi apparatus membranes b. the internal face of a lysosome membrane c. facing the intermembrane space of the nuclear envelope membranesd. the lumen face of a vesicle just derived from the Golgi apparatus .e. the cytosolic face of the plasma membrane

Answer 1

Answer: Option E.

The cytosolic face of the plasma membrane.

Explanation:

Endoplasmic recticulum is a membranous organelles in cytoplasm that help in synthesis,transport and modifications of proteins. Proteins are transported to golgi apparatus while some remain in endoplasmic reticulum. Proteins are transported from ribosomes on rough endoplasmic recticulum to rough endoplasmic recticulum lumen which is the site of protein modifications, then to golgi aparathus.