Which type of fatty acids contains one or more double bonds?

Monounsaturated fatty acids are characterized by having one double bond in their carbon chain. The presence of this double bond introduces a kink in the fatty acid structure, which can affect the physical properties of the fat, such as its melting point. These types of fatty acids are typically found in higher amounts in plant oils, such as olive oil, and are known for their health benefits, including potential cardiovascular protection.

On the other hand, polyunsaturated fatty acids contain two or more double bonds. Saturated fatty acids do not contain any double bonds; they are fully saturated with hydrogen atoms, making them typically solid at room temperature. Trans fatty acids can have one or more double bonds, but the unique geometric configuration of the trans form affects how the body metabolizes them, often leading to adverse health effects. Thus, the accurate identification of monounsaturated fatty acids as containing one double bond sets them apart clearly from these other types.