What constitutes the outer coat of lipoproteins?

What constitutes the outer coat of lipoproteins?

• A. phospholipids, cholesterol and proteins
• B. triglycerides only
• C. cholesterol only
• D. nucleic acids and proteins

Answer: (D)

Lipoproteins have a hydrophobic core filled with triglycerides and cholesteryl esters, surrounded by a single-layer surface composed of phospholipids, cholesterol, and apolipoproteins on the outside. This outer coat is amphipathic: the phospholipid heads face the aqueous blood, while the tails help enclose the core, and the apolipoproteins on the surface act as ligands for receptors and help enzymes access the particle. That means the outer coat is best described by phospholipids, cholesterol, and proteins. Triglycerides sit inside the core, and nucleic acids are not a component of lipoproteins.

Lipoproteins have a hydrophobic core filled with triglycerides and cholesteryl esters, surrounded by a single-layer surface composed of phospholipids, cholesterol, and apolipoproteins on the outside. This outer coat is amphipathic: the phospholipid heads face the aqueous blood, while the tails help enclose the core, and the apolipoproteins on the surface act as ligands for receptors and help enzymes access the particle. That means the outer coat is best described by phospholipids, cholesterol, and proteins. Triglycerides sit inside the core, and nucleic acids are not a component of lipoproteins.