Cholesterol is best described as which of the following?

• A. One of the sterols, manufactured in the body for a variety of purposes
• B. A carbohydrate
• C. A mineral
• D. A protein

Answer: (A)

Cholesterol is a sterol, a type of lipid produced by the body for a variety of essential roles. As a sterol, it has a characteristic four-ring structure and a hydroxyl group, which allows it to be integrated into cell membranes and to serve as a precursor for several important molecules. The liver largely makes cholesterol, and it also comes from the diet. It is a key building block for bile acids and steroid hormones and supports membrane integrity. It is not a carbohydrate (carbohydrates are mainly energy sources), not a mineral (minerals are inorganic elements), and not a protein (proteins are made of amino acids).