Which statement best describes monounsaturated fatty acids?

Which statement best describes monounsaturated fatty acids?

• A. zero double bonds
• B. two double bonds
• C. one double bond
• D. three double bonds

Answer: (C)

Monounsaturated fatty acids are defined by having a single carbon–carbon double bond in their hydrocarbon chain. That one double bond introduces a kink in the chain, which prevents tight packing of the molecules and lowers the fat’s melting point, making the fat more fluid than saturated fats at room temperature. This is why monounsaturated fats are typically liquid oils like olive oil. If there were zero double bonds, the fatty acid would be saturated, packing more tightly and having a higher melting point. If there were two or more double bonds, it would be polyunsaturated. The statement that best describes monounsaturated fatty acids is that they have one double bond.

Monounsaturated fatty acids are defined by having a single carbon–carbon double bond in their hydrocarbon chain. That one double bond introduces a kink in the chain, which prevents tight packing of the molecules and lowers the fat’s melting point, making the fat more fluid than saturated fats at room temperature. This is why monounsaturated fats are typically liquid oils like olive oil. If there were zero double bonds, the fatty acid would be saturated, packing more tightly and having a higher melting point. If there were two or more double bonds, it would be polyunsaturated. The statement that best describes monounsaturated fatty acids is that they have one double bond.