Which of the following phospholipids is localized to a greater extent in the outer leaflet of the membrane lipid bilayer?
(A) Choline phosphoglycerides
(B) Ethanolamine phosphoglycerides
(C) Inositol phosphoglycerides
(D) Serine phosphoglycerides
The correct answer is indeed (A) Choline phosphoglycerides, such as phosphatidylcholine.
Phosphatidylcholine, also known as lecithin, is a type of phospholipid that prefers to be located in the outer leaflet (also known as the outer monolayer) of the membrane lipid bilayer. This is due to its molecular structure, which has a positively charged choline head group that interacts favorably with water and the external environment.