Which of the following is the most important component of pulmonary surfactant?
I.Dipalmitoyl phosphatidylcholine
II.Phosphatidylglycerine
III.Phosphatidylinositol
IV.Sphingomyelin

Question

Quizplus · Accepted Answer

Surfactant composition is fairly constant among mammalian species.Surfactant is composed of approximately 90% lipids (of which 80% to 85% are phospholipids)and approximately 10% proteins (see Table 14-1 in the textbook).Phosphatidylcholine (PC)is the most abundant phospholipid (75% to 80%)and is mostly saturated (40% to 55%)in the form of dipalmitoyl phosphatidylcholine (DPPC).DPPC is the most important surfactant component in reducing surface tension;it consists of two molecules of palmitic acid and one molecule of phosphatidylcholine attached to a glycerol backbone.DPPC has a hydrophobic end (fatty acids)and a hydrophilic end (nitrogenous base)and aligns itself in the air-liquid interface with the hydrophobic end toward the gas phase and the hydrophilic end toward the liquid phase.

Which of the Following Is the Most Important Component of Pulmonary