What are plaques?

• A. Lipid deposits
• B. Blood clots
• C. Calcium deposits
• D. Fibrous tissue

Answer: (A)

Plaques in this context are lipid deposits that accumulate in the inner lining of arteries during atherosclerosis. They start when LDL cholesterol infiltrates the arterial intima and is taken up by macrophages, forming foam cells and expanding into fatty streaks. Over time, this lipid-rich material is surrounded by connective tissue and smooth muscle cells to form a plaque. While plaques can accumulate calcium and develop a fibrous cap as they mature, the defining feature being described here is their lipid content. Blood clots are a separate event that can occur if a plaque ruptures, and calcium or fibrous tissue can be parts of a plaque, but the essential characteristic highlighted is the lipid deposits.