Waxes are a type of lipids.

• A. Complex lipids
• B. Proteins
• C. Nucleic acids
• D. Simple lipids

Answer: (D)

Waxes are esters formed from a fatty acid and a long-chain alcohol, which places them in the simple lipids group. Simple lipids are esters of fatty acids with alcohols and do not include the extra polar head groups found in complex lipids. Waxes differ from fats (triglycerides) that have a glycerol backbone attached to three fatty acids, and they lack the phosphate or sugar-containing components characteristic of complex lipids. Proteins and nucleic acids aren’t lipids at all—they’re built from amino acids and nucleotides, respectively. The long hydrocarbon chains in waxes give them a waxy, water-repellent quality and a protective coating function, aligning neatly with the simple lipid category.