Which of the following statement is correct about membrane cholesterol?
(A) The hydroxyl group is located near the centre of the lipid layer
(B) Most of the cholesterol is in the form of a cholesterol ester
(C) The steroid nucleus form forms a rigid, planar structure
(D) The hydrocarbon chain of cholesterol projects into the extracellular fluid
The correct statement about membrane cholesterol is:
(C) The steroid nucleus forms a rigid, planar structure.
The steroid nucleus of cholesterol indeed forms a rigid, planar structure that helps maintain membrane fluidity and stability. The hydroxyl group of cholesterol is located near the membrane surface, and most cholesterol in membranes is not in the form of cholesterol ester. The hydrocarbon chain of cholesterol also does not project into the extracellular fluid; it is embedded within the lipid bilayer.