Final answer:
Essential fatty acids, such as alpha-linolenic acid and linoleic acid, are polyunsaturated fats that must be obtained through the diet because the body cannot synthesize them. They are necessary for the structure and function of cell membranes, hormone synthesis, and metabolism of cholesterol. Key dietary sources include plant oils, nuts, seeds, whole grains, and leafy vegetables.
Step-by-step explanation:
Essential fatty acids (EFAs) are types of polyunsaturated fats that the human body cannot synthesize on its own and therefore must be obtained from the diet. These include omega-3 fatty acids like alpha-linolenic acid (ALA) and omega-6 fatty acids like linoleic acid. The EFAs play crucial roles in various physiological processes such as cell membrane structure, immune system function, and the production of eicosanoids, which regulate inflammatory processes.
Option 1 correctly lists essential fatty acids: Linoleic acid and Alpha-linolenic acid, while Arachidonic acid can be synthesized from linoleic acid. These EFAs contribute to membrane fluidity and hormone synthesis. Option 4 also lists some EFAs but includes the category "Omega-3" generally, which is not a specific fatty acid.
Functions attributed to EFAs include the synthesis of long-chain unsaturated fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from ALA, though this conversion is inefficient, suggesting dietary intake of these long-chain acids is beneficial. EFAs are also involved in the transport and metabolism of cholesterol and are required for normal growth and development.
Food sources of linoleic acid include corn oil and soybean oil, while ALA is found in nuts, flaxseed, whole grains, and green leafy vegetables. A daily diet should encompass 4–6 grams of these essential fatty acids to maintain health.