What fatty acid contains double bonds?

• A. saturated
• B. phospholipid
• C. unsaturated
• D. amino acid

Answer: (C)

Double bonds in the fatty acid chain define unsaturated fatty acids. In saturated fatty acids, every carbon is linked by single bonds and the chain is fully saturated with hydrogens, so there are no double bonds. When one or more double bonds are present, the fatty acid is unsaturated, which changes the shape of the chain and affects properties like melting point. A phospholipid is a different type of molecule that includes fatty acids as part of its structure, but it’s not itself a fatty acid. An amino acid is unrelated to fatty acids and is a building block of proteins.