New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Exam 2 study guide

by: Marygrace Restaino

Exam 2 study guide NUTR 295

Marketplace > George Mason University > NUTR 295 > Exam 2 study guide
Marygrace Restaino

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

these cover all of her slides
Nutrition and Food Studies
Alicja Terzian
Study Guide
50 ?




Popular in Nutrition and Food Studies

Popular in Department

This 23 page Study Guide was uploaded by Marygrace Restaino on Monday April 11, 2016. The Study Guide belongs to NUTR 295 at George Mason University taught by Alicja Terzian in Spring 2016. Since its upload, it has received 45 views.


Reviews for Exam 2 study guide


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 04/11/16
Exam 2 Review Questions NUTR 295 Chapter 5 The Lipids 1. What is the definition of lipids? Their solubility in water and in organic solvents.  Lipid: a family of 9organic containing) compounds soluble in organic solvents but not in water. Lipids include triglycerides (fats and oils), phospholipids, and sterols. 2. Most of the lipids in our food are present in one form of lipid. Which one?  95% of lipids are triglycerides 3. What are the roles of lipids in both the body and foods?  Shock absorbers: for internal organs  Provide insulation: against extreme temperatures  Cell membranes: main components  Transport: carry fat-soluble vitamins A D E K and some phytochemicals, other fats  Raw Materials: for steroid hormones, bile, vitamin D, and other compounds synthesis  Important nutrients: provide essential fatty acids  Facilitate absorption: of fat soluble nutrients  Signaling: eicosanoids act as hormones  Sensory qualities: aromas, flavors, tenderness  Fat contributes to satiety: slows down food movement  Concentrated calorie source o1g fat = 9 cal o1g CHO = 4 cal o1g Protein = 4 cal 4. Triglycerides structure and function.  Triglycerides: one of the three main classes of dietary lipids and the chief form of fat in foods and in the human body. A triglyceride is made of three units of fatty acids and one unit of glycerol.  Saturated fats are solid at room temperature 5. Saturated vs unsaturated fatty acids, trans fats. Which foods contain them?  Saturated fats: solid at room temperature. A fatty acid carrying the maximum possible number of hydrogen atoms. (having no point of unsaturation) a saturated fat is triglyceride that contains 3 fatty acids.  Unsaturated fats: liquid at room temperature. A fatty acid that lacks some hydrogen atoms and has one or more points of unsaturation. An unsaturated fat is a triglyceride that contains one or more unsaturated fatty acids. 6. What are phospholipids? Their role, cell membrane  Phospholipids: one of the three main classes of dietary lipids. These lipids are similar to triglycerides, but each has a phosphorus-containing acid in place of one of the fatty acids. Phospholipids are present in all cell membranes.  Phospholipids soluble in fat and water  Emulsifier  Phospholipid bilayer  Generate signals inside the cell in response to hormones  Hydrophobic tail; hydrophilic head 7. Cholesterol, its role in the body.  Component of the cell membrane  Compounds made from cholesterol: oBile acids oSteroid hormones (testosterone, estrogen) oVitamin D oCholesterol is not an essential nutrient 1. Your liver produces enough from CHO, protein, and fat  Bile salts: are the oxidation products of cholesterol. Synthesized in the liver. Stored in the gallbladder. Secreted into intestines where they emulsify dietary fats and aid in their digestion. 8. Describe the difference between LDL and HDL in terms of cholesterol and protein composition.  Lipoprotein: clusters of protein and phospholipids that act as emulsifiers- they attract both water and fat to enable their large lipid passengers to travel in the watery body fluids  LDL (Low density lipoproteins): lipoproteins that transport lipids from the liver to other tissues such as muscles and fat; contain a larger proportion of cholesterol. Made from VLDL in the circulation after they donated many of their triglycerides to the body cells  HDL (high density lipoproteins): lipoproteins that return cholesterol from the tissues to the liver from dismantling and disposal; containing large proportion of proteins. Reverse cholesterol transport. Made in liver. Cholesterol excreted as bile 9. What foods contain cholesterol?  Egg yolks, milk products, meat, poultry, shellfish 10. Name the two essential fatty acids. What is their role in the body?  Omega -3: Linolenic acid; a polyunsaturated fatty acid with its endmost double bond three carbons from the end of the carbon chain.  Omega -6 : Linoleic acid; a polyunsaturated fatty acid with its endmost double bond six carbons from the end of the carbon chain  Roles: oProvide raw material for eicosanoids oServe as structural and functional parts of cell membranes oContribute lipids to the brain and nerves oPromote growth and vision oAssist in gene regulation oMaintain outer structures of the skin, thus protecting against water loss oHelp regulate genetic activities affecting metabolism oSupport immune cell function 11. How lipids (TAG) are digested? What facilitates lipid digestion? Where is most of the digestive enzyme activity?  Starts in mouth and stomach (little digestion)  Digestive enzymes accomplish most fat digestion in the small intestine. There, bile emulsifies fat, making it available for enzyme action. The enzymes cleave triglycerides into free fatty acids, glycerol, and monoglycerides  Digestion of triacylglycerol by pancreatic lipase 12. How are lipids absorbed? What is the absorbable unit of triglycerides?  At the intestinal lining the parts are absorbed by the intestinal villi. Gycerol and short-chain fatty acids enter directly into the bloodstream  The cells of the intestinal lining overt large lipid fragments such as monoglycerides and long chain fatty acids back into triglycerides and combine them with protein, forming chylomicrons (a type of lipoprotein) that travel in the lymph vessels to the bloodstream  In the small inttestines a small amount of cholesterol is trapped in fibber exits with the feces  Intestinal villi take up digested emulsified by bile fat molecules 13. After absorption, which system(s) carry the lipids in the body?  Lymph  Bloodstream 14. How are lipids (and fat-soluble molecules) transported in the water-based blood?  Lipoproteins attract both water and fat to enable their large lipid passengers to travel in the watery body fluids 15. What is a lipoprotein? List the four main types of lipoproteins. Where in the body are they synthesized? What is the function of each? Which is commonly called “good cholesterol” and which is called “bad cholesterol”?  Lipoprotein: clusters of proteins and phospholipids that act as emulsifiers: a substance that mixes with both fat and water and permanently dispenses the fat in the water, forming an emulsion. oChylomicrons: lipoproteins formed when lipids from a meal cluster with carrier proteins in the cells of the intestinal lining. Chylomicrons transport food fats through the watery body fluids to the liver and other tissues made inside enterocytes oVLDL (very low density lipoproteins) : lipoproteins that transport triglycerides and other lipids from the liver to various tissues in the body. Made in liver oLDL (low density lipoproteins): lipoproteins that transport lipids from the liver to other tissues such as muscle and fat, contain a large proportion of cholesterol. LDL are made from VLDL in the circulation after they have donated many of their triglycerides to the body cells oHDL (high density lipoproteins): lipoproteins that return cholesterol from the tissues to the liver for dismantling and disposal, containing a large proportion of protein. Cholesterol is excreted as bile. Made in liver. Reverse cholesterol transport 16. Dietary Recommendations  What % of kcals should come from total, saturated, and trans fats? o20-35% of kcals from fat mostly unsaturated oSaturated less than 105 KCALS oTrans as low as possible  What should you consider when buying margarine? oBuy soft instead of hard oChoose <2 g saturated fat oAvoid hydrogenated or partially hydrogenated fats, at least as the first ingredient oTry olive oil  What are the pitfalls of a low-fat diet for weight loss? oNot enough protein onot eating enough fat to make you full otoo much fruit onot a lot of non starchy veggies otoo much starchy veggies Chapter 6 The Proteins 1. Describe the basics of the chemical nature of amino acids and proteins  amino acids = protein building blocks  20 amino acids  Proteins are made up of about 20 common amino acids.  Proteins are compounds composed of hydrogen oxygen and nitrogen arranged as strands of amino acids. Some contain sulfur  Amino acids: the building blocks of protein. Each has an amino group at one end, an acid group at the other, and a distinctive side chain. a. What is the name of the bond linking amino acids in a polypeptide chain?  Peptide bonds b. The importance of the side “R” group of the amino acid.  Side chain electrical charge  Activation 2. What is an essential amino acid?  Amino acids that either cannot be synthesized in amounts sufficient to meet physiological needs. 3. What is protein denaturation?  The irreversible change in a protein’s folded shape brought about by heat, acids, bases, alcohol, salts of heavy metals or other agents.  Unfolding, changing a protein’s folded shape  Denaturation permits digestive enzymes to make a contact with the peptide bonds and cleave them 4. Digestion, absorption and transport of proteins  Where does protein digestion start? oStomach. Strong acid denatures proteins in food. Uncoil protein’s strands oEnzymes- pepsin- attacks peptide bonds  Where does the bulk of protein digestion occur? oSmall intestines: single amino acids and larger polypeptides are digested by pancreatic enzymes- trypsin oFurther break down by peptidases on the surface of the small intestines cells  What is the absorbable form of proteins? oAbsorbed by cells of small intestines 1. There are at least four sodium-dependent amino acid transporters- one each for acidic, basic, neutral and imino acid. oNo absorption of peptides longer than four amino acids. 1. There are abundant absorption of di and tripeptides in the small intestines. Once inside the enterocyte, the vast bulk of absorbed di and tripeptides are digested into amino acids by cytoplasmic peptidases and exported from the cell into the blood oNeonates have the ability to absorb intact proteins oCarried to liver  Do absorbed amino acids enter the blood or the lymph? oblood 5. What is protein turnover?  In healthy individuals the total amount of protein in the body remains constant  This is because the rate of protein synthesis is sufficient to replace the protein degraded  Amino acids conserved from protein degradation provide raw material for new proteins  On average 300 to 400 g of the body protein each day are degraded and resynthesized  This process of breakdown, recovery, and synthesis is called protein turnover 6. What are the functions of protein in the body?  Providing structure and movement oMuscle tissue (about 40% body’s proteins exist in muscle tissue) oOther structural proteins (in cartilage, blood vessels, bones, teeth and other tissues)  Building enzymes  Building hormones  Other compounds oNeurotransmitters (epinephrine, norepinephrine, serotonin)  Building antibodies oLarge proteins of the blood, produced by the immune system in response to an invasion of the body by foreign substances- antigens 1. Each antibody destroys one specific invader  Transporting substances: hemoglobin and lipoproteins  Maintaining fluid and electrolyte balance (proteins attract water)  Proteins transport substances into and out of cells  Maintaining acid-base balance (acids and bases are constantly produced by the body, blood carries them for excretion, blood proteins act as buffers) oBuffers (maintain blood’s normal pH) 1. Acidosis 2. Alkalosis  Blood clotting (special proteins prevent blood loss in injury by clotting the blood)  Providing energy: with inadequate supply amino acids are converted to glucose 7. What are the fates of amino acids?  Cellular use oBuild protein oMake a needed compound (hormone, antibody..) oDismantle amino acid to build a different amino acid  Wasting of Amino Acids oFour conditions 1. Lack of energy from other sources 2. Excess of protein in the diet 3. Too much of an amino acid from supplement 4. Dietary protein of low quality oPreventing waste (supple dietary protein in adequate quality and amount accompanied by CHO and fat) 8. Protein quality  What does protein quality measure? (two things) oAmino acid composition 1. High quality protein = dietary proteins containing all the essential amino acids in relatively the same amounts that humans require oProtein digestibility: depends on protein sources and cooking methods  Generally speaking, which foods contain high quality protein? Which foods contain low quality protein? oHigh: animal foods: eggs, meat, fish, poultry, dairy, soy protein oLow: plant proteins: veggies, nuts, seeds, grains, legumes  Describe what is meant by ‘complementary proteins’. Do they have to be eaten together at every meal? oComplementary proteins: mix and match your plant proteins to ensure that you get enough of each AA 9. What are the risks and/or benefits or consuming more protein than you need?  Protein Excess: oWeight loss 1. Reduce calorie intake from all sources of food oHeart disease 1. Animal-derived protein-rich foods, processed foods oAdult bone loss oCancer 10. Dietary recommendations  How much protein does an average person need? o78 grams/day  What % of kcals should come from protein? o10-35% kcals  Do Americans get adequate protein in our diets, on average? oAmericans eat too much 11. Which food groups (in general) provide protein?  Animal proteins: 90-99%  Plant proteins: 70-90%  Beef  Poultry  Milk  Yeast bread  Cheese  Fish  Pork  Eggs  Pasta  Ham  Cakes  Beans Chapter 7 The vitamins 1. What is a vitamin? What is a provitamin, a precoursor?  Essential, noncaloric, organic nutrient needed in tiny amounts in the diet  Vitamin presursors in foods are transformed into active vitamins by the body i. Ultraviolet rays act on cholesterol compound in the skin producing D precursors, absorbed by blood, then 1. Liver and kidneys convert the inactive precursor to active vitamin D 2. Sunlight presents no risk of toxicity 3. Variables affecting D synthesis: geography, season, time of day , air pollution, clothing, tall buildings, indoor living, sunscreen. 2. Compare and contrast fat-soluble and water-soluble vitamins. a. Which are fat soluble? Which are water soluble?  Fat soluble vitamins are A D E K  Water soluble vitamins are C and all B b. Digestion and absorption  Water soluble vitamins are absorbed directly into the bloodstream. Do not require proteins for transport in the blood. Not stored in the body. Excess is excreted by kidneys. Easily destroyed/lost during food processing  Fat soluble: follow same path as large fats: require bile for absorption, absorbed into the lymphatic system c. Transport in the body  Water soluble is transported by bloodstream  Fat soluble: require proteins for transport in blood d. Storage in the body  Water soluble Not stored in the body  Excess stored in the liver and adipose tissue e. Toxicity  Water soluble is harder to develop toxicity than ADEK. Easier to develop deficiencies than fat soluble  Fat soluble is easy to reach toxic level from supplements (not food) 1. Not easily excreted: builds up in tissue f. Deficiency  Water soluble Easily destroyed/lost during food processing  Don’t need to be consumed everyday 3. Good food sources of all the vitamins.  Vitamin D (fat): naturally: i. egg yolk, oily fish ii. Fortified: milk, cereals  Vitamin K i. Made in GI tract ii. Dark green leafy greens, vegetables oils, eggs  Vitamin A (fat): whole fat milk, liver, fish, eggs, butter i. Fortified margarine, enriched skim milk ii. Pro-vitamin sources- beta carotene and others (from plants) 1. Color: deep orange, yellow fruits veggies 2. Dark green leaves  Vitamin C (water): fruits, veggies, white potatoes. Destruction through heat oxygen light.  Vitamin B (water): grains, fruits, veggies, meat, milk, eggs  Vitamin A (fat): from animals, provide forms of vitamin A that are readily absorbed and put to use by the body i. Foods derived from plants provide beta carotene which must be converted to active vitamin A ii. Three active forms 1. Retinol 2. Retinal 3. retinoic 4. Major functions of all the vitamins.  Vitamin K i. Active proteins that help clot the blood ii. Necessary for the synthesis of key bone proteins  Vitamin E (fat) i. Antioxidant: fights with free radicals 1. Prevents damage to PUFAs in lipoproteins in blood and cell membranes, DNA, working proteins 2. May reduce risk of heart disease by preventing oxidation of LDL  Vitamin D i. Body can synthesize all it needs 1. Sunlight ii. Drop in blood vitamin D levels caused by: 1. Obesity: adipose tissue traps vitamin D 2. People spend less time outdoors 3. Diet low in fat, strict vegetarian diet iii. Blood calcium and phosphorus levels regulation 1. Acts at three locations to raise calcium level in blood: skeleton, digestive tract, and kidneys iv. Acts as a hormone (compound manufactured by one organ of the body that acts on the other organs), is involved with gene regulation, affects how cell grow, multiply and specialize v. Is important to bone growth and maintenance  Vitamin A (fat soluble) i. Vision (light and color) ii. Gene regulation: protein synthesis iii. Cell differentiation iv. Immune function v. Supports reproduction and growth (bone, teeth) vi. In short, vitamin A is needed everywhere vii. Beta-carotene (provitamin A) is an antioxidant  Vitamin C (water soluble): i. Maintains connective tissue. Participates in the synthesis of collagen (acts as cofactor of enzyme). ii. Antioxidant fights free radicals iii. Protects iron from oxidation and promotes absorption iv. Vital to immunity  Vitamin B (water) i. Function as part of coenzymes 1. Combine with enzymes to activate it 2. Coenzyme shape 3. Roles in metabolism: help body to metabolize CHO, lipids, and amino acids and use them as fuel 4. Build new cells ii. Riboflavin (b2) 1. In energy metabolism of all cells, important coenzyme in redox reactions iii. Niacin (b3) 1. Participates in energy metabolism by assisting other B vitamins in converting carbohydrates to glucose and in metabolism of fat 2. The amino acid tryptophan can be converted to niacin in the body. A person eating adequate protein will not be deficient in niacin iv. Folate (B9) 1. Helps to synthesize DNA, amino acids, new cells, its metabolism depends on the presence of vitamin b12 2. Work together with vitamin B12 in producing red blood cells 3. Among all vitamins folate is most likely to interact with medications lowering the body use of folate v. Cobalamin (B12) 1. Role: helps maintain and protect the sheaths around nerve fibers. Necessary for folate metabolism. Necessary for maturation of erythrocytes vi. Pyridoxine (B6) 1. Participates in over 100 reactions vii. Biotin (b7) and Pantothenic Acid (b5) 1. B7 a. Cofactor for enzyme in the metabolism of carbohydrates fat proteins b. Gene expression 2. B5 a. Key coenzyme participates in more than 100 steps in the synthesis of lipids, neurotransmitters, steroid hormones, and hemoglobin 5. Major signs/symptoms of deficiency and toxicity.  Vitamin K i. Rarely from poor dietary intake 1. More often from: fat malabsorption; bile production fails making lipids, including all of the fat-soluble vitamins, unabsorbable 2. Interfere with bacterial production (antibiotics) ii. Newborns born with sterile GI tract, single dose of vitamin K given at birth (injection or oral) iii. Toxicity 1. Rare a. Jaundice 2. Can reach toxic levels in pregnancy and infants, with supplements  Vitamin E i. Deficiency not seen in healthy individuals ii. Toxicity rare 1. Extremely high doses as in supplements may interfere with blood-clotting action of vitamin k; enhance anti-clotting meds like Coumadin  Vitamin D i. Deficiency: 1. Rickets in children bowed legs a. Recommendations for prevention cod- liver oil, sunlight exposure, fortified milk 2. Osteomalacia a. Bones less mineralized, painful, soft, deformed bones 3. Osteoporosis a. Loss of calcium from the bones resulting in fractures ii. Toxicity 1. Most potentially toxic vitamin 2. Increases blood calcium (hypercalcemia) concentrations and damage soft tissues i. Kidney and heart failure 3. Risk of high doses: high blood calcium, nausea, fatigue, back pain, irregular heartbeat, and increased urination and thirst 4. Risk of moderate doses: taken over months or years, may be linked with an increased risk of diseases, falls, and fractures, and even an increased risk of death  Vitamin A (fat) i. Stored in liver, therefore do not need to consume everyday 1. Deficiency symptoms may not appear for 1- 2 years for adults not consuming vitamin A. not a problem in us but is in developing countries ii. Failure to grow is also one of the first signs of poor vitamin A status in a child due to abnormal bone growth iii. Increased risk of mortality from infectious disease iv. Abnormal function of many epithelial cells v. Vitamin A toxicity: overstimulating cell division 1. Skin rashes 2. Hair loss 3. Hemorrhages 4. Bone abnormalities 5. Fractures 6. Liver failure 7. Death 8. Not likely to occur in regular food. Too much beta carotene turns you orange  Vitamin C (water) i. Little storage capabilities ii. Rare to see toxicity 1-2 grams (1000-2000 mg) per day iii. Deficiency: scurvy: causes breakdown of collagen. Red bleeding spots  Vitamin B (water): i. Deficiencies: rarely occur alone, except in beriberi and pellagra 1. Every cell affected 2. Muscle weakness, no appetite, degeneration, confusion, exhaustion, irritability, immune response impaired ii. Riboflavin (b2) 1. Deficiencies: glossitis and cheilosis; elderly people, poor diet. 2. Destruction of vitamin: UV light, irradiation iii. Niacin (b3) 1. Deficiency: pellagra: diarrhea, dementia, dermatitis, death (alcoholism/genetic disorder) 2. Toxicity: large doses of niacin cause liver injury, digestive upset, impaired glucose tolerance 3. Niacin flush causes dilation f capillaries of the skin with tingling sensation iv. Folate 1. Common in pregnant women and alcoholics 2. Impaired absorption, alcoholism, increase demand- pregnancy lactation 3. Outcomes of deficiency: megaloblastic anemia: large, immature red blood cells- megaloblasts, due to inhibition of dna synthesis during red blood cell production. 4. Birth defects: neural tube defects 5. Toxicity: 1000 micrograms for adults; increase risk of cancer, high intake can mask blood symptoms of vitamin B12 deficiency v. Cobalamin (B12) 1. Deficiency caused by decreased or absent intrinsic factor/HCL a. Elderly (decreased production) b. Stomach/ small intestine surgeries c. Prolonged use of antacid drugs 2. Pernicious anemia (large, immature red blood cells) a. Deficient intrinsic factor b. Alcoholism c. Elderly 3. Nerve damage vi. Pyridoxine (b6) 1. Deficiencies: weakness, confusion, irritability, insomnia, anemia, dermatitis, weak immune system 2. Toxicity: more than 2 grams/day for few months: numb feet sensation in hands. Unable to walk. vii. Biotin (b7) and Pantothenic Acid (b5) 1. Available in foods. 6. What is meant by vitamin “equivalents” or “International Units”?  Equivalents: a new measure of the vitamin A activity of beta carotene and other vitamin A precusors that reflects the amounts of retinol that the body will derive from a food containing vitamin A precursor compounds  International Units: a measure of fat soluble vitamin activity sometimes used in food composition tables and on supplement labels 7. Which vitamins can be made within the body? 8. What is an antioxidant? Which vitamins can act as antioxidants? What roles do antioxidants have in the body and in health promotion?  Antioxidants fight free radicals  Vitamin c  Protects iron from oxidation and promotes its absorption  Vital to immunity 9. What is meant by the “interdependence” of the B vitamins?  The presence of one b vitamin may affect the absorption, metabolism and excretion of another  A deficiency of one may affect the functioning or deficiency of another 10. What are the two main roles of the family of B vitamins?  Every cell affected  Muscle weakness, no appetite, degeneration, confusion, exhaustion, irritability, immune response impaired 11. Deficiencies of which B vitamins can cause anemia?  Who is at risk for these deficiencies? i. All of them 12. What is the general relationship between alcoholism and the B vitamins?  Alcoholism can cause deficiencies 13. What does folate have to do with spina bifida?  Neural tube defects. Deficiencies range from slight problem with spine to mental retardation, severely diminished brain size and death shortly after birth 14. What is special about B 12 food sources?  No plant source  Synthesized through microorganisms  Occurs only in animal products: eggs, meat, poultry, milk, shellfish  Fortified cereals  Supplements Chapter 8 Water & Electrolytes Water: 1. Functions of water o Solvent  Transport vehicle for all the nutrients and wastes o Participates in metabolic reactions o Maintains blood volume o Lubricant  Lubricates the digestive tract, the repertory tract, and all tissues that are moistened with mucus o Cushion  For joints, spinal cords, other internal organs, fetus o Coolant  Maintains body temperature  Sweat (sweat evaporates, heat energy dissipates, cooling the skin and the underlying blood) 2. Sources of water o Ingested foods and liquids (performed water) o Metabolic water produced during dehydration synthesis of anabolism o Water and beverages (near 100%) o Fruits veggies (90%) o Meats and cheeses (50%) o Generates during metabolism (metabolic water) o An intake of 2800 mililiters of water is usually represented by  Liquids 1500 ml  Foods 1000 ml  Metabolic water 300 ml 3. Water loss, intake and thirst 4. Dehydration: how the body maintains water balance? o Water balance: the balance between water intake and water excretion  The body controls both intake and excretion to keep the water content constant o The brain and the kidneys regulate the water content in the body o Eating a meal high in salt can temporarily increase the body’s water content; the body sheds he excess over the next day or so as the sodium is excreted  These temporary fluctuations in body water shown on the scale, but gaining or losing water weight does not reflect a change in body fat o Water balance:  Dehydration: too much water is lost from the body and when is not replaced, dehydration can threaten survival  Signs: thirst, weakness, exhaustion, delirium and death o Thirst is a conscious desire to drink and is regulated by the mouth, hypothalamus, nerves, and pituitary gland  Water intake low- blood becomes concentrated, mouth dry, hypothalamus initiates drinking. kidneys conserve water  water intake is high- stomach expands and stretch receptors signal to stop drinking  if you are thirsty you are already dehydrated o water intoxication: containing too much water in the body  rare  Usually involves consuming several gallons of plain water in a few hours  Blood is dangerously diluted 5. Water recommended intake (what factors influence water intake?) o Depends on diet, activity, environment, humidity, air temp o 2-3 liters (8-12 cups) for 2000 kcals expenditure o Total water AL males: 3.7 L/day (13 cups) o Total water AL females: 2.7 L/day (9 cups) 6. What fluids should you drink? o Water and non-caloric beverages o Avoid large quantities of sugar sweetened drinks o Our tap water is cleanest and safest o Bottled water 7. What are electrolytes? How does the body regulate electrolytes? o You get them from foods you eat and the fluids you drink o Levels of electrolytes in your body can become too low or too high. That can happen when the amount of water in your body changes causing dehydration or overhydration o Causes include some medicines, vomiting, diarrhea, sweating or kidney problems Major Minerals and Trace Minerals 1. Identify the major and trace minerals in the human body. a. Trace minerals: needed in tiny quantities i. Iodine 1. Part of hormone thyroxine made by thyroid gland a. Thyroxine regulates bodys metabolic rate body temperature, reproduction, growth, heart functioning 2. Deficiency: lethargy, forgetfulness, cold, weight gain, goiter. Cretinism ii. Iron 1. Every cell contains iron 2. Two proteins a. Hemoglobin in red blood cells b. Myoglobin in muscle cells 3. Roles: a. Iron in hemoglobin carries oxygen from the lungs to tissues throughout the body and carbon dioxide from the tissues to the lungs. b. Iron in myoglobin holds and stores oxygen in the muscles for their use. c. Iron is a cofactor of many enzymes involved in energy metabolism. iii. Zinc 1. Works with proteins in every organ and tissue 2. Functions (literally hundreds – up to 300 have been studied extensively): a. Protects from oxidation b. Cofactor in many enzymes c. Part of proteins associated with DNA d. Regulate protein synthesis and cell division e. Needed for active form of vitamin A f. Immune system g. Affects behavior, learning, and mood iv. Selenium 1. Roles: a. Protects vulnerable body molecules against oxidative destruction. b. c. Works with vitamin E, limits the formation of free radicals and prevents oxidative harm to cells and tissues. d. e. Part of enzymes that assist thyroid hormone in regulation of metabolism. v. Fluoride 1. Not essential to life 2. Beneficial- in prevention of dental caries 3. Roles in the body a. Fluorapatite for tooth development and growth. b. Inhibits metabolism and growth of bacteria that causes cavities. c. Deficiency d. Dental decay e. Toxicity (when water contains too much fluoride) f. Fluorosis – spotty teeth vi. Chromium vii. Copper viii. Manganese ix. Molybdenum b. Major minerals: are found in large quantities in the body i. Calcium 1. 99% in body found in bones and teeth 2. 1% in fluids and cells 3. Most abundant mineral in the body 4. Two roles of bone calcium: a. Integral part of bone structure b. Serves as a bank that can release calcium to the body fluids 5. The minerals of bones are in constant flux (entire adult human skeleton is remodeled every 10 years) 6. Roles in body fluid a. Disease prevention: may protect against hypertension, high blood cholesterol, diabetes, and colon cancer b. Blood clotting c. Muscle contraction d. Regulates the transport of ions across cell membrane e. Nerve transmission f. Secretion of hormones, digestive enzymes and neurotransmitters g. Activation of cellular enzymes that regulate many processes 7. Amount of calcium in the blood is tightly controlled by a complex hormone system 8. Calcium balance: a. The key to bone health lies in the body’s calcium balance, directed by a system of hormones and vitamin D b. Three organ systems quietly respond: i. Intestines: increase absorption of calcium from the intestines ii. Kidneys: prevent loss in urine iii. Bones: release more calcium into the blood c. Parathyroid hormone: regulates reabsorption of calcium from bone and reabsorption of calcium in the kidneys back to circulation d. Vitamin D3: promotes absorption of calcium from intestines and mobilization of calcium from bone matrix ii. Chloride 1. Crucial for fluid balance 2. Major anion 3. Hydrochloric acid in stomach 4. Sodium chloride iii. Magnesium 1. Half in bones 2. The rest in muscles, heart, liver, soft tissue, 1% body fluids 3. Bones and kidneys regulate magnesium levels in blood 4. Roles: a. Works with calcium in muscle contraction/relaxation b. Bone and teeth health (holds calcium in bones and tooth enamel) c. Energy metabolism d. Assists > 300 enzymes e. Blood pressure f. Legumes, seeds, nuts, greens, veggies, dairy iv. Phosphorus 1. Second most abundant in body a. Majority found in bones and teeth b. 85% combines with calcium for structure 2. Roles: a. Phosphorus salts are critical buffers: maintain acid base balance of cellular fluids b. Part of rna and dna c. Carry store and release energy in metabolism of energy nutrients d. Components of cell membranes v. Potassium 1. Positively charged 2. Roles: a. Maintain fluid and electrolyte balance b. Trades place with sodium during impulse transmission of muscle contraction c. Maintain cell integrity d. Maintain steady heartbeat vi. Sodium 1. Principal cation of extracellular fluid 2. Primary regulator of blood volume and fluid balance 3. Nerve impulse transmission 4. Muscle contraction vii. Sulfate 1. Abundant in water and foods 2. Made from amino acids in dietary protein c. Inorganic elements i. Retain their chemical identity when exposed to heat, air, acid, or mixing ii. Only lost when they leach into water 2. Roles of the minerals in the body. a. Major mineral functions: i. Maintain fluid balance (sodium, chloride, potassium) ii. Bone growth, cell metabolism, and health (calcium, phosphorus, magnesium) 3. Consequences of their deficiency. 4. Toxicity. a. Calcium: from supplements, kidney stones, interfere with absorption of other minerals, constipation b. Magnesium: rare but fatal i. Salt laxitatives ii. Diarrhea, dehydration, disrupts ph balance iii. Toxic to liver c. Sodium: vomiting diarrhea heavy sweating d. Potassium: nt possible with food. Injected into vein stops heart 5. Food sources and recommended intake.


Buy Material

Are you sure you want to buy this material for

50 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Anthony Lee UC Santa Barbara

"I bought an awesome study guide, which helped me get an A in my Math 34B class this quarter!"

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.