Steroid hormones are derived from which molecule?

• A. Glucose
• B. Cholesterol
• C. ATP
• D. Lipase

Answer: (B)

Steroid hormones are lipid-soluble messengers that come from cholesterol, which provides the four-ring backbone essential for all steroids. The synthesis begins with cholesterol being converted in the mitochondria to pregnenolone, and then enzyme-specific steps produce the various steroid hormones like cortisol, aldosterone, and the sex steroids. The other molecules listed aren’t building blocks for steroid hormones: glucose is a carbohydrate used for energy and biosynthesis, ATP is the cellular energy currency, and lipase is an enzyme that breaks down fats, not a precursor for steroid production. So cholesterol is the correct starting molecule.