NUTR SCI 132 Lecture 14 Outline of Last Lecture I. Proteina. Requirements vs Intakeb. Sourcesc. Protein QualityII. VegetariansIII. Protein DeficiencyIV. LipidsOutline of Current Lecture I. Lipidsa. Three Typesi. Triglyceridesii. Phospholipidsiii. Sterolsb. Usesc. Digestion and AbsorptionCurrent LectureI. Lipids (Fatty Acids)a. Three Typesi. Saturated vs. Unsaturated Fatty Acid pictureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.1. Saturated = linear molecule, Hydrogens completely surround Carbon Moleculesa. Contributes to risk of Heart Diseaseb. Solid at room temperaturei. Found in warm-blooded animals2. Unsaturated = double bonds break up straight chain and disallow Hydrogens from completely saturating the moleculea. Helps decrease risk of Heart Diseaseb. Liquid at room temperature i. Kinks in chain make substance harder to crystalizeii. Found in fishc. Monounsaturatedi. One point of unsaturation (one double bond)ii. Canola and Olive Oild. Polyunsaturatedi. More than one point of unsaturationii. Omega 3 (Alpha-linolenic acid) vs. Omega 6 (Linoleic Acid)1. Name based on how far double bond is from the end of chainii. Trans-fatty acids1. Product of Hydrogenationa. Converts Unsaturated fat into saturated fatb. Bubble oil in Hydrogen gas i. Cis bond to trans bond1. Affects on body are worse than saturated fat!ii. Why do they do this? 1. Changes property of substance2. Vegetables used to be less expensive than saturated fats but saturated fats make nicer texture for cookingiii. Hydrogenated or partially hydrogenated is your clue on food labels!iii. Triglycerides1. Saturated, Unsaturated and Trans-fatty acid2. Glycerol head and 3 chains3. 98% iv. Phospholipid1. Close to Triglyceridesa. Glycerolb. 3rd fatty acid chain has Phosphorus on end instead (Phosphate compound)2. Not essential nutrient (we can synthesize)3. Found in:a. Cell membranesb. Lecithin (salad dressings)i. Emulsifier made from soy beans v. Sterols1. Cholesterola. Found only in animalsb. Used for steroid Hormonesc. We synthesize this; do not need to eat any of it!b. Usesi. Energy1. 9kcal/grama. Most energy dense of all macronutrients!2. Storage form of energya. Most lightweight form of energyb. Adipose tissue (Body Fat)i. Shock absorptionii. Thermal Insulationiii. Regular Menstruation for women1. Estrogen metabolized in adipose tissue2. Irregular Menstruation danger sign for boneloss!iv. >10% for menv. +5-7% for menii. Cell Membranesiii. Eicosanoids1. Regulatory compoundsi. Vascular dilationii. Immune responseiii. Blood Pressure2. Chemical messengers in bodya. Local effect (vs. Hormones)i. Blood Clottingii. Inflammation3. Made from long-chain polyunsaturatediv. Essential Fatty Acids1. Body cannot synthesize omega-3 or omega-6 fatty acidsa. BUT, we can elongate them2. Linoleic (Omega-6)3. Alpha-Linolenic Acid (Omega-3)v. Cholesterol1. Steroid Hormonesa. Estrogenb. Testosteronec. Vitamin D2. Bile3. Cell Membranesc. Digestion and Absorptioni. Fats Insoluble in water1. Fat encapsulated inside villi of Mucosa of small intestine by chylomicrons to be transported in blood streama. Deliver lipids to liveri. Very Low Density Lipoproteins (VLDL) transport:1. In liver, translated before Triglycerides delivered to cellsa. Dietary (Fat eaten)b. Endogenous (synthesized)ii. Low Density Lipoproteins (LDL)1. Deliver cholesterol to cells and arteriesa. Dietary and endogenous2. Atherogenic (“bad cholesterol”)a. Contributes to risk of heart attackiii. High Density Cholesterol (HDL)1. Good
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