Certified Dietary Manager (CDM) Practice Exam

Which type of fatty acid contains more than one double bond?

1. Monounsaturated fatty acid

2. Saturated fatty acid

3. Polyunsaturated fatty acid

4. Trans fatty acid

The correct answer is: Polyunsaturated fatty acid

Your selection is indeed accurate. A polyunsaturated fatty acid is characterized by having two or more double bonds in its carbon chain. This structure is significant as it impacts the fatty acid's physical properties and nutritional value. Polyunsaturated fatty acids are typically found in various plant-derived oils, fish, and certain nuts and seeds, and they play essential roles in human health, including promoting heart health and reducing inflammation. In contrast, a monounsaturated fatty acid has only one double bond, which distinguishes it from polyunsaturated fatty acids. Saturated fatty acids, on the other hand, contain no double bonds at all, as their carbon chains are fully saturated with hydrogen atoms. Trans fatty acids are another category that usually results from the hydrogenation process of unsaturated fats, converting them to a more stable form but not necessarily indicating the number of double bonds present in the original fatty acid structure. Thus, the definition and structure of polyunsaturated fatty acids clearly support the correct answer.