Exam 2 Study Guide Lipids Functions of lipids Nature s way of condensing energy stores Also insulates and protects organs Source of calories 9Kcal gram Provides flavor and tenderness of food Slows stomach emptying more satiating Source of essential fatty acids Types of Lipids Phospholipids cell membranes Sterols hormones Triglycerides predominant in food 95 Phospholipids Sterols Glycerol 2 fatty acids phosphorus Phosphorus part makes this soluble in water Fatty acid part makes it soluble in fat Can serve as an emulsifier of carbon hydrogen and oxygen attached Cholesterol Large molecules consisting of interconnected rings of carbon atoms with side chains Found in all animal cell membranes Nonessential Forms plaques that cause athrosclerosis Serves as raw material for bile vitamin D steroid hormones Triglycerides Main form of fat in food Glycerol backbone and 3 fatty acids Classified by length of carbon atoms the location of the double bonds and the organization of hydrogen around the double bonds Saturated Fatty Acids Maximum number of hydrogen atoms Unsaturated Fatty Acids Less then maximum hydrogen atoms Monounsaturated 1 double bond Polyunsaturated 2 or more double bonds Found in soft solids or liquids Trans Fatty Acids Fatty acids with unusual shapes Polyunsaturated oils that are hydrogenated control consistency and oxidation of fats Found in margarines shortenings and baked goods increase LDL Essential Fatty Acids Made in limited amounts in the body Abundant in fish oils Lower blood pressure Prevent blood clot formation Protect against irregular heartbeats May reduce inflammation Essential for normal infant growth development May support immune system May inhibit cancers Omega 3 Fatty Acids Linolenic Acid Found in tuna salmon herring flax see canola soybean oils almonds walnuts spinach mustard greens Reduce inflammation blood clotting and tumor growth Omega 6 Fatty Acids Linoleic Acid Found in grains fats and oils Cause inflammation blood clotting and tumor growth Eicosanoids hormone like compounds that are made from EEFAs and act through receptors on tissues to regulate many body responses Digestion Depends on Pre duodenal Lipase gastric Pancreatic lipase Bile acids for emulsification Absorption Short chain fatty acids Portal vein blood to liver Monoglycerides and longer fatty acids Lipase breaks down triglycerides into free fatty acids and monoglycerides Get repackaged as triglycerides for transport in chylomicrons Enter lymph then the blood stream Transport as Lipoproteins Chylomicrons from the intestine to the body Other produced in the liver VLDLs very low density lipoproteins BAD LDLs low density lipoproteins BAD Both triglycerides and cholesterol to the body HDLS High density lipoproteins GOOD Scavengers of cholesterol brings it back to the liver Total cholesterol Less than 200 is desirable 200 239 is borderline bad 240 and above is BAD Proteins and Amino Acids What do proteins do Build tissue growth or replacements of parts enzymes hormones antibodies fluid electrolyte balance acid base balance energy transportation blood clotting structural components How much do we need DRI recommendation is dependent on size and stage of growth DRI recommendation of 8 grams per kg of body weight Minimum is 10 of total calories Athletes may need slightly more 1 gram per kg Classification of amino acids Essential 9 histidine isoleucine leucine lysine methionine phenylaline threonine tryptophan and valine Nonessential 11 Protein Denaturation Heat acid alcohol base salts Vitamins Organic compounds contain carbon many different structures form simple to complex Non caloric Essential lack of vitamins leads to deficiency syndromes can not be synthesized in the body with exceptions Needed in small amounts Classification Fat soluble Vitamins A D E and K Absorbed like dietary fat requires bile Carried in the blood using protein carriers Can be stored in body fat mainly liver Generally have greater body stores then water soluble High likelihood of toxicity Water soluble Thiamin riboflavin niacin pantothenic Acid B6 C Vitamin A Functions Toxicity Generally have lower body stores then fat soluble vitamins Usually excreted in urine Low in toxicity Eyesight gene regulation cell differentiation immune function growth of bone and teeth From fortified foods Concern of pregnant women children and adolescents From Accutane Beta Carotene Antioxidants Vitamin A precursor found in plants water soluble low in toxicity found in bright orange fruits and vegetables and leafy greens Many carotenoids but beta carotene is the most abundant Prevents free radicals from causing damage to body structures such as cell membranes and DNA Vitamin C E zinc selenium copper and phytochemicals Free Radical Damage Molecules often oxygen with unpaired electrons that cause damage to the body s structures Sources mitochondria immune system pollutants cigarette smoke Cell membranes and lipids causing cells lysis Inactivation and degradation of proteins and enzymes Damage to DNA Chain rxn road block antioxidants Diseases associated heart cancer aging cataracts Fortified milk carrots beef liver sweet potatoes apricots Regulated blood calcium and phosphorus levels Helps to maintain bone integrity Stimulates maturation of cells including immune cells Acts on genes affecting how cells grow and multiply diseases cancer multiple sclerosis Highly toxic Deficiency Rickets Poor bone mineralization Body weight causes legs to bow Sources Fortified milk salmon shrimp liver SUNLIGHT Sources Vitamin D Functions Vitamin E Functions Sources Vitamin K Functions Vitamin C Functions Sources Folic Acid Folate Functions Sources Functions Functions B6 B12 Thiamin Functions Sources Protects cell membranes Regulates oxidation reactions Antioxidant lungs RBC immune cells brain cells Canola oil safflower oil mayonnaise wheat germ sunflower seeds Synthesis of blood clotting Synthesis of proteins important to bone mineralization Made by intestinal bacteria Newborns given a dose of VK at birth Antibiotic overdose can lead to VK deficiency Sources Cabbage spinach soybeans canola oil salad greens Assists in enzyme involved in the formation and maintenance of collagen wound healing acts as an antioxidant especially protecting the immune system cells from free radical generation smokers should take more to counter act free radicals Sweet potatoes strawberries broccoli brussel sprouts Part of a coenzyme needed for new cell synthesis Asparagus avocado beets
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