What does LDL cholesterol represent?

What does LDL cholesterol represent?

• A. High-density lipoprotein that removes cholesterol from tissues.
• B. Low-density lipoprotein that delivers cholesterol to tissues; elevated levels contribute to plaque buildup and atherosclerosis.
• C. Very-low-density lipoprotein that transports triglycerides.
• D. Cholesterol ester that circulates in plasma without lipoproteins.

Answer: (B)

LDL cholesterol represents the low-density lipoprotein particle that carries cholesterol from the liver to tissues throughout the body. This delivery role means LDL supplies cholesterol for cell membranes and steroid hormone synthesis, but when levels are high, more LDL particles circulate and can infiltrate artery walls. There, LDL can become oxidized and be taken up by macrophages, forming foam cells and contributing to the fatty plaques of atherosclerosis. This connection to plaque buildup is why LDL is considered the “bad” cholesterol. HDL, in contrast, helps remove cholesterol from tissues and return it to the liver, which is why it’s viewed as protective. Very-low-density lipoprotein mainly transports triglycerides, not cholesterol delivery to tissues, and cholesterol esters don’t circulate on their own without a lipoprotein carrier.

LDL cholesterol represents the low-density lipoprotein particle that carries cholesterol from the liver to tissues throughout the body. This delivery role means LDL supplies cholesterol for cell membranes and steroid hormone synthesis, but when levels are high, more LDL particles circulate and can infiltrate artery walls. There, LDL can become oxidized and be taken up by macrophages, forming foam cells and contributing to the fatty plaques of atherosclerosis. This connection to plaque buildup is why LDL is considered the “bad” cholesterol.

HDL, in contrast, helps remove cholesterol from tissues and return it to the liver, which is why it’s viewed as protective. Very-low-density lipoprotein mainly transports triglycerides, not cholesterol delivery to tissues, and cholesterol esters don’t circulate on their own without a lipoprotein carrier.