DIT 121 Exam 2 | 100% Correct | Verified | 2024 Version

DIT 121 Exam 2 | 100% Correct | Verified | 2024 Version What are the 3 main classes of lipids? - triglycerides: the most common type of lipid in food and the body phospholipids: for example, in cell membranes sterols: include cholesterol, vitamin D, some hormones. what is the main form of fat in the diet and the major storage form of fat in the body? - triglycerides what 2 types of molecules (and how many of each) join together to forma triglyceride? - glycerol + 3 fatty acids explain what is meant by saturated, monounsaturated, and polyunsaturated when referring to fatty acids. - monounsaturated: fatty acids have 1 double bond between carbons polyunsaturated: fatty acids have 2 or more double bonds between carbons saturated: no double bonds omega-3 fatty acids - have the 1st double bond after the 3rd carbon, counting from the methyl (CH3) group omega-6 fatty acid - have the 1st double bond after 6th carbon, counting from the methyl group which type of fatty acids (saturated or unsaturated) tend to make fats solid at room temperature? - saturated: saturated with hydrogens unsaturated: not saturated with hydrogen, can hold more hydrogen which types of fatty acids (saturated/unsaturated) tend to make fats liquid soft at room temperature - saturated fatty acids stack together, make fats solid at room temperature: animal fat, bacon grease, lard, chicken fat, butter unsaturated fatty acids: dont stack neatly, making fats soft or liquid at room temperature: avocado, fatty fish, nuts and seeds, olives, vegetable oils. what is hydrogenation, and why is this done to the oils in processed foods? - hydrogenation produces trans-fatty acids; "trans-fat" are oils to which H atoms have been added. where does most chemical digestion and absorption of fats occur? - small intestine 10. What role does bile have in fat digestion? What do lipases from the pancreas do to digest fats? - - Emulsifies fat, breaks fat into small fat globules so enzymes can act better. - Break triglycerides into glycerol and fatty acids. 10. Which lipids are absorbed without further digestion? - - Cholesterol, fatty acids, glycerol, medium chain triglycerides (MCT), monoglycerides 14. What are the main functions of lipids in the body? - The omega-3 fatty acids DHA and EPA are important for: - Normal growth - Brain development - Cognitive development - Health of retinas in eyes - Visual acuity - Provide energy - Part of adipose tissue: Energy reserve, insulation, shock absorber 15. What is the role of HDL? How does it affect heart disease risk? - Liver makes it, remove cholesterol from the cells and carry it back to the live for recycling or disposal. Lowers the effect of heart disease. 15. What are DHA and EPA? What do these do in the body? (p. 149) - - DHA: an omega-3 polyunsaturated fatty acid with 22 carbons and six double bonds; present in fatty fish and synthesized in limited amounts in the body from linolenic acid. - EPA: an omega-3 polyunsaturated with 20 carbons and five double bonds; present in fatty fish and synthesized in limited amounts in the body from linolenic acid. 15. The USDA's Dietary Guidelines recommend that we eat less solid fats. What kinds of foods give: - - Butter, shortening, palm oil, fat around meat. ~ raise blood cholesterol 15. What factors lower LDL and/or raise HDL? (see p. 147) - 15. at factors lower LDL and/or raise HDL? (see p. 147) - Eating healthy fats, nuts seeds, lean meats, fish - Reducing sugar - exercise 15. According to the DRI and the USDA Dietary Guidelines, what is the recommended intake of each of the following: - - total fat (as %