part LIPIDS 1, Chapter 5 1. Define: lipid, lipophilic, eicosanoids, micelle and emulsifier, saturated, monounsaturated, polyunsaturated, hydrogenated (as they relate to fatty acids), cholesterol, essential fatty acids, cisfatty acids and trans-fatty acids. a. Lipid- A diverse group of organic substances that are insoluble in water; lipids include triglycerides, phospholipids, and sterols. a.i. Triglycerides- A molecule consisting of three fatty acids attached to a threecarbon glycerol backbone. a.ii. Phospholipids- Soluble in water; egg yolks, peanuts, soybeans; glycerol backbone with fatty acids attached at first and second carbons and another compound that contains carbon attached at the third carbon; help with transport of substances into and out of the cell membrane; digestion of dietary fats a.iii. Sterols- A type of lipid found in foods and the body that has a ring structure; cholesterol is the most common sterol that occurs in our diets. b. Lipophilic- Attracted to fat b.i. Fat loving c. Eicosanoids- Synthesized from fatty acids with twenty carbon atoms, helps to regulate gastrointestinal tract motility, secretory activity, blood clotting, vasodilatation and vasoconstriction, vascular permeability, and inflammation. Produced in nearly every cell in the body. d. Micelle- A spherical compound made of bile salts and biliary phospholipids that transport lipid digestion products to the intestinal wall. e. Emulsifier- Helps to keep fats evenly dispersed within foods into goblets. Chemicals that improve texture and smoothness in foods; stabilize oil-water mixtures. f. Saturated- Fatty acids that have no carbons joined together with a double bond; these types of fatty acids are generally solid at room temperature: coconut oil, butter, cheese, whole milk, and cream. g. Monounsaturated- Fatty acids that have two carbons in the chain bound to each other with one double bond; these types of fatty acids are generally liquid at room temperature: olive oil, canola oil. h. Polyunsaturated- Fatty acids that have more than one double bond in the chain; these types are generally liquid at room temperature: cottonseed, canola, corn, and sunflower oil. i. Hydrogenated (as they relate to fatty acids)- Process of adding hydrogen to unsaturated fatty acids, making them more saturated and thereby more solid at room temperature: greater saturation. i.i. Adding hydrogen to Polyunsaturated fatty acids i.i.1. More Solid i.i.2. More Stable i.i.3. Increased health risk- trans fat i.ii. The fatty acid may be hydrogenated or partially hydrogenated j. Cholesterol- Most common sterol; used for sex hormones, adrenal hormones, and vitamin D. The precursor for the bile salts that are a primary component of bile, which helps emulsify the lipids in the gut prior to digestion. Essential to human health. k. Essential Fatty Acids- Fatty acids that must be consumed in the diet because they cannot be made by the body; linoleic (omega-6) acid and alpha-linolenic acid (omega-3).
l. Cis-fatty Acids- Has both hydrogen atoms located on the same side of the double m.
bond, naturally occurring geometric orientation of unsaturated fats. Trans-fatty acids- Hydrogen atoms are attached on diagonally opposite sides of the double carbon bond; Isomer of cis that is produced by an artificial process of saturating the fatty acids with hydrogen in vegetable oils called hydrogenation. m.i. Shortening m.ii. More stable than cis m.iii. Higher melting point than cis m.iii.1. Found in margarines, shortenings, commercial frying fats and baked goods m.iii.2. increase risk of heart disease
2. Describe differences in structure, functions, characteristics, and chemical properties of
lipids and fatty acids. Recognize and identify chemical structures of the different lipids and fatty acids, include alpha and omega ends, and locations of double bonds. When given a chemical structure, be able to name type of fatty acids; for example monounsaturated fatty acid or omega 3 fatty acid. a. Lipids a.i. Tryglyceride a.ii. Functions a.ii.1. Essential Nutrients a.ii.2. Energy source in foods a.ii.3. Energy reserve in animals a.ii.4. Insulation and protection a.ii.5. Carrier of fat-soluble compounds a.ii.6. Sensory qualities a.ii.7. Satiety a.iii. Structure: 3 fatty acids and 1 glycerol a.iv. Characteristics: most common form in foods b. Fatty Acids b.i. All have an acid end and a methyl end b.ii. All have a carbon chain b.iii. Degree of saturation varies b.iv. Length of carbon chain varies c. Saturated: maximum number of hydrogen atoms, Palmitic acid c.i. All carbons c.ii. Saturated with hydrogen atoms c.iii. Form single bonds with another c.iv. Pack tightly together c.iv.1. Properties c.v. Stable to heat and air... long shelf life c.v.1. Generally solid at room temperature c.v.1.a. Exception: short chained fatty acids... tend to be more liquid c.v.1.b. Ex. c.v.1.b.i. Animal fats and oils c.v.1.b.i.1. Butter, lard c.v.1.b.i.2. coconut, palm oil
d. Monounsaturated: 1 double bond, "missing" 2 hydrogen atoms d.i. One place of unsaturation d.ii. Double bond between 2 carbon atoms d.iii. Oleic Acid (omega-9) d.iv. Contains one Carbon bond in the carbon chain d.iv.1. Loss of hydrogen atoms d.iv.2. Do not pack tightly together d.v. Properties d.v.1. Liquid at room temperature, solid at refrigerated
temperatures Example d.v.2.a. Oils: olive, canola d.v.2.b. Some in animal fats Polyunsaturated e.i. 2 or more double bonds, "missing" 4, 6, 8.... hydrogen atoms e.i.1. 2 or more areas of unsaturation e.i.2. Double bonds between 2 carbons e.i.3. Contains 2 or more double bonds at carbon chain e.i.4. Do not pack tightly together e.i.4.a. Properties e.i.4.a.i. Liquid at room temperature e.i.4.a.ii. Liable to heat and air e.i.4.a.ii.1. Example e.i.4.a.ii.1.a. Vegetable oil, corn and sunflower seeds e.i.4.a.ii.1.b. Cold water fish Phospholipids f.i. Functions f.i.1. Emulsifier, help in digestion of dietary fats f.ii. Structure f.ii.1. 2 fatty acids, 1 glycerol, and 1 phosphate group f.iii. Characteristics f.iii.1. Helps regulate the transport of substances in and out of cell in the cell membrane hydrophobic tail, hydrophilic end Sterols g.i. Functions g.i.1. Cholesterol g.ii. Structure g.ii.1. Multiple rings g.iii. Characteristics g.iii.1. Hormones, vitamin D Methyl Group= CH3 h.i. Start counting with the carbon of the Methyl group h.ii. Carboxly Group= COOH h.iii. Count the number of carbons until you reach the first double bond.
d.v.2.
e.
f.
g.
h.
3. Describe the basic structure, significance, and examples of phospholipids and sterols that
are important in human nutrition.
4. Explain the functions of fat. 5. Describe the role that bile plays in the digestion and absorption of lipids. Include
information on how bile functions as an emulsifier.
6. Identify food sources of visible and invisible fat, cholesterol, saturated fat,
monounsaturated fat, and polyunsaturated fat. a. Visible Fat- fats we knowingly add to foods: butter, cream, mayo. b. Invisible Fat- Fats hidden in foods: baked goods, dairy, processed meats. c. Cholesterold. Saturated Fat- (every carbon atom in the chain has max amount of hydrogen bonded to it): butter, milk, beef. e. Monounsaturated Fat- (in the chain of carbon atoms, two carbons are bonded together and excludes hydrogen): olive oil, cashews, canola oil. f. Polyunsaturated Fat- (more than 1 double bond) cottonseed, canola, corn and sunflower oils.
7. Define: lipid, lipolysis, eicosanoids, micelle, cardiovascular disease, heart attack, stroke,
plaques and emulsifier.
8. Explain the digestion, absorption, synthesis and breakdown of triglycerides 9. Explain the structure and functions of lipoproteins involved in lipid transport. Distinguish
between the various types. Discuss the beginning location and route of travel for each; LDL vs HDL in heart disease. a. A lipoprotein is a spherical compound with triglycerides clustered in the center along with cholesterol esters, free cholesterol, and other hydrophobic lipids, and phospholipids and proteins forming the outside of the sphere. The specific lipoprotein produced in the enterocytes to transport lipids from a meal is called chylomicron. b. Majority of lipid absorption occurs in the mucosal lining of the small intestine with help of micelles (made of bile). Within the enterocytes, fatty acids and monoglycerides are made back into triglycerides and packaged lipoproteins, as which canmix with water to travel into the bloodstream. c. LDL: high in cholesterol, phospholipids, and protein; as they circulate the blood, they deliver cholesterol to cells will LDL receptors. Diets high in saturated fat decrease the removal of LDLs by body cells, which block these sites. If the LDLs are not taken up by the blood cell, the LDLs degrade over time and release their cholesterol, resulting in an increased load of cholesterol in the blood; this increase ups the chances that some of it will stick to the walls of the blood vessels, which can turn to plaque that eventually blocks the artery. LDL increases risk of heart disease (Page 193-195) d. HDL: small, dense lipoproteins with a very low cholesterol content and high protein content. Released from the liver and pick up cholesterol from dying cells and plaques and transfer it to other lipoproteins which return it to the liver. Liver uses this to synthesize bile; HDLs are associated with a low risk of coronary artery disease.
10. Discuss the significance of LDL and HDL in heart disease.
a.
11. Discuss the nutritional significance and food sources of omega 3s and omega 6s in
human nutrition. When given a chemical structure, be able to name polyunsaturated fatty acids (i.e., omega 3) a. Omega 3: seafood, canola, soybean oils, flax, walnut, leafy greens; reduces triglycerides in blood, may inhibit cancer development b. Omega 6: sunflower, corn, soybean oils; deceases blood LDL cholesterol, encourages clot formation b.i. intake omega 6 to omega 3 is 4:1
12. For cardiovascular disease: describe the development of the disease, risk factors, and
relationship to diet including the role of the different lipids and fatty acids. a. High LDL levels increase risk for heart disease, while high HDL decreases risk b. Risk factors: overweight, physical inactivity, smoking b.i. High intakes of saturated and trans-fatty acids increase blood levels of those lipids associated with heart disease.
13. Specify the dietary recommendations that have been made for the various types of lipids. a. Make fat 20-35% of calories; minimize saturated ad trans fatty acids; saturated <
7% total calories, cholesterol less than 300 mg per day, 20-30 grams of dietary fiber per day, 400 micrograms a day of folate. (20-25% from fat 55-60% from carbs, 1215% from protein) Linoleic acid: 14-17g for men, 11-12g for women (5-10% of energy) Alpha-linoleic: 1.6g for men, 1.1g for women (.6%-1.2% of energy)
b. c.
PROTEINS, Chapter 6 1. Identify differences in structure between proteins, lipids and carbohydrates. a. 2. Describe the primary, secondary, tertiary and quaternary structures of protein. (Pg 216) a. Primary: Amine Group b. Secondary: Acid Group c. Tertiary: Hydrogen Atom d. Quaternary: A side chain (the unique part)
3. Define denaturation and explain how proteins may be denatured. a. Denaturation: Process by which proteins uncoil and lose shape and function when
exposed to heat, acids, bases, heavy metals, alcohol and other damaging substances. (Cooking an egg)
4. Discuss the activation of pepsinogen to pepsin. Include the concept of self-digestion. a. Pepsinogen to Pepsin a.i. Protein reaches stomach and HCL denatures the protein strands and
converts inactive enzymes into pepsin; its considered self-digestion because pepsin is a protein, it's just a protein-digesting enzyme
5. State the major determinates of protein quality. a. Quantity of essential amino acids: higher protein quality foods are those that b.
contain more essential aminos in sufficient quantities to build proteins. Digestibility: higher digestion rate is more complete
6. Know the location in the GI tract, enzymes and end products of protein digestion. 7.
a. Discuss functions of proteins and give examples of each. a. Cell growth, repair and maintenance; embryo; constant replacement and growth of new cells and proteins to create a new human body.
8. Discuss the amino acid pool, protein turnover, and the use of amino acids to make 9. 10. 11.
nonessential amino acids or proteins. Describe what happens when the amino acid pool does not contain all amino acids. Discuss nitrogen balance. Give examples of individuals that are likely to be in each type of balance. Describe the process of protein synthesis. (remember the animation is available to help you understand this) Distinguish between essential and nonessential amino acids. List essential amino acids. a. Essential Amino Acids: Cannot be produced by body so must be taken in by food a.i. ex. histidine, isoluecine, leucine, lysine, methionine, phenylalanine, thereonine, tryptophan, valine b. Nonessential Amino Acids: Body can synthesize them in sufficient quantities so we do not need to consume them in our diet.
12. Compare foods for their protein content, quality, and cost. Name foods that supply
complete proteins and foods that supply incomplete protein. a. Complete: milk, yogurt, cheese, meat, poultry, fish, eggs, soy, quiona b. Incomplete: dried beans, nuts, veggies, bread, cereal, rice, pasta c. Quality: Ability of a protein to support growth c.i. Completeness c.ii. Digestibiblty d. Good combos: grains and legumes, vegetables and legumes, grains or nuts and seeds
13. Discuss and recognize examples of complementary proteins. a. Good combos: grains and legumes, vegetables and legumes, grains or nuts and
seeds
b. Peanut Butter Sandwich (wheat bread), hummus and bread, bean burrito, rice and
beans
14. Distinguish between vegans, ovo-vegetarians, lacto-ovo-vegetarians and semi 15. 16. 17.
vegetarians; know the foods that would be included or excluded and the limiting nutrients associated with each type of diet. Describe the health benefits and risks associated with a vegetarian diet. Discuss the differences between marasmus and kwashiorkor. List recommendations for dietary intakes of protein (DRI/RDA and % kcal). Calculate protein needs when given the weight for an individual.
METABOLISM, Chapter 7 1. Define: glycolysis, glycogenolysis, gluconeogenesis, lipogenesis, metabolism, anabolism, catabolism, urea, transamination, deamination, ketosis and coenzyme. 2. Discuss the path of the macronutrients from the breakdown products of digestion through energy production. Include the TCA cycle, the electron transport chain, ATP and the role of the B vitamins.
3. Describe the steps in the metabolism of glucose. State the number of carbons in each
step. 4. Discuss the location in the cell where steps occur, the role of oxygen status for each step, the starting and end products for each step and conditions influencing the end products. List which steps are reversible and which intermediate products can be used to make glucose. 5. Identify the structure and components of triglycerides. Describe steps in the metabolism of triglycerides, state the number of carbons in each component and in each step of metabolism, identify the place of entry into the metabolic pathway. Identify which component can be used to make glucose and which cannot. 6. Discuss the significance of oxaloacetate, what can happen if the body runs short of the needed amount of oxaloacetate and how such a shortage might occur. 7. Describe the metabolism of amino acids, state the place of entry into the metabolic pathway and the possibilities for making glucose. 8. Describe the synthesis of protein. 9. Identify the connection between protein, ammonia and urea, the site of urea formation and the site of urea excretion. 10. Explain the body's storage pathways for energy yielding nutrients. 11. Describe the effect of feasting (overeating) on metabolism and what happens during short and long-term fasts. 12. List and discuss the functions performed by the liver. Nutrients of Energy Metabolism, Chapter 8 1. Define/or explain: macronutrient, micronutrient and coenzyme. 2. List and describe the properties of vitamins. Discuss the need for vitamins in a healthful diet. 3. Compare the properties of fat vs. water soluble vitamins. 4. List ways that vitamin content can be decreased. 5. List ways to preserve vitamin content in foods. 6. For thiamin, riboflavin, niacin, and iodine a. Explain the major function b. List major food sources c. List the major deficiency diseases 7. Summarize why the B vitamins are important in energy metabolism. Name the vitamins that participate in energy metabolism. 8. Discuss the relationship between alcoholism and thiamin.