Nutrition Flashcards

Transcription

1 1. Is the bloodstream water based or lipid based? Water based 2. How are lipids transported in the bloodstream? By water-soluble carriers that have a lipophilic region 3. What are lipid carriers called? Lipoproteins 4. What are the four major groups of lipoproteins, in order of size, from largest to smallest? Chylomicrons VLDL (very low density lipoproteins) LDL (low density lipoproteins) HDL (high density lipoproteins) 5. How are LDL particles formed? when lipoprotein lipase breaks a triglyceride molecule off VLDL 6. Why are LDL called bad cholesterol? higher levels of LDL particles promote health problems and cardiovascular disease 7. What is cholesterol? a waxy steroid of fat that is produced in the liver or intestines 8. What is cholesterol used for? 1) to produce hormones A) steroid hormones (including cortisol and aldosterone) B) Sex hormones (progesterone, estrogens, testosterone) 2) To establish proper cell membranes membrane permeability and fluidity 3) To make bile 4) To make one vitamin (vitamin D) 9. How is cholesterol recycled? In the liver, cholesterol is converted to bile, which is then stored in the gallbladder. It is the excreted into the digestive tract, and about 50% of it is reabsorbed back into the bloodstream. 10. What is the function of bile? Bile contains bile salts, which emulsify fats in the digestive tract to aid in the intestinal absorption of fat molecules as well as the fat-soluble vitamins, A, D, E, and K. 11. How does a cell obtain cholesterol? it synthesizes the necessary LDL receptors, and inserts them into the plasma membrane. LDL particles which are carrying cholesterol in the blood stream bind to these extracellular LDL receptors and the cholesterol is brought into the cell and either used or stored. The LDL receptors are then removed from the plasma membrane. 12. Why is LDL called bad cholesterol? It can transport cholesterol into artery walls. 13. What happens when the cholesterol in the arterial wall becomes oxidized by a free radical (a circulating H + ion)? it hardens and forms a plaque (atherosclerosis). 14. What can happen to a plaque? It can break off and travel in the bloodstream as a fat embolism, lodge in a smaller blood vessel, and block blood flow distal to that point. 15. What happens if this occurs in the brain? Stroke 16. What happens if this occurs in the coronary arteries? Heart attack

2 17. What predicts whether or not cholesterol is High levels of LDL transported into artery walls? 18. What popular medicine group is prescribed for Statins (such as vasostatin). people with high LDL levels? 19. How do these medicines work? By inhibiting cholesterol synthesis 20. If cholesterol synthesis is inhibited, what levels Triglycerides will go up; seen in a blood test. will become elevated in the blood if the person does not cut back on their fat consumption? 21. What are triglycerides? They are the main constituents of saturated and unsaturated fat. 22. What is the function of triglycerides? They are a mechanism for storing unused calories 23. What are triglycerides correlated with? The consumption of starch and fatty foods 24. How are triglycerides useful? They transport dietary fat to cells that need it 25. What happens to triglycerides in the small They are converted to chylomicrons, which are intestine? absorbed by lacteals (lymph vessels) 26. What is the enzyme that breaks down Lipase triglycerides so they can be absorbed in the small intestine? 27. What is the most effective dietary approach to Minimizing fat stores in the greater omentum (reduce minimize LDL s in the blood? fat in the waistline) in addition to minimizing total 28. What are two reasons why is it worse to have a fat belly than to have fat in the rear end, regarding LDL levels? 29. Why is it worse to have a fat belly than to have fat in the rear end, regarding diabetes? 30. What obvious appearance is an indicator of how high your LDL and triglyceride levels are, and therefore, is an indicator of cardiovascular health? 31. What other lipid can be lowered which will reduce LDL levels? How to you lower that lipid? 32. Are LDL particles harmless until they are within the blood vessel walls and oxidized by free radicals? 33. Will ingesting antioxidants, thereby minimizing free radical exposure reduce LDL's contribution to atherosclerosis? 34. Why are HDL particles called "good cholesterol"? body fat. 1) Fat stored in the greater omentum is mobilized before subcutaneous fat (deep to the dermis). Fat stored in the rear end is subcutaneous fat. Therefore, fat stored in the omentum will be made into LDL first. 2) Greater omentum fat also produces an enzyme called resistin, which lowers circulating VLDL concentrations (which increases LDL levels). Resistin also increases insulin resistance (causing Diabetes Mellitus) Having a large waist line Triglycerides. Lower them by consuming less fat. Yes Possibly...clinical studies are inconclusive. HDL particles are able to remove cholesterol from within arterial plaques and transport it back to the liver for excretion or re-utilization

3 35. Will increasing one's HDL beyond normal No limits make you healthier than normal? 36. Where does HDL transport cholesterol? Mostly to the liver or organs that use cholesterol such as adrenal glands, ovaries, and testes. 37. What happens to the cholesterol delivered to It is combined with broken-down hemoglobin and the liver? converted into the bile, which is then used to break down intestinal fats into small enough particles for digestive enzymes to work. 38. What happens to the cholesterol delivered to It is used for the synthesis of steroid hormones. adrenal glands, ovaries, and testes? 39. What three properties of HDL contribute to its inhibits oxidation, inflammation, and coagulation by ability to protect from atherosclerosis? platelets 40. Can you increase HDL by exercise? No, your levels are hereditary 41. What three things may increase HDL levels? Niacin (vit B3) and magnesium, Apo-A1. Note: Vitamin C does not raise HDL levels. 42. What are the two categories of triglycerides? Saturated and unsaturated fatty acids 43. What are examples of each? Vegetable oil (typically unsaturated) Animal fats (typically saturated) 44. What is the function of triglycerides? They are a mechanism for storing unused calories 45. What causes high levels of triglycerides in the consumption of starchy and fatty foods blood? 46. Are triglycerides directly absorbed in the small No, they are too large. intestine? 47. How are triglycerides absorbed? The pancreatic enzyme lipase acts releases the fatty acids so they can be absorbed (lipolysis). 48. How are triglycerides broken down? They are broken down to fatty acids and then the fatty acids are absorbed by the small intestine. 49. How much energy to they contain, compared to More than twice as much carbohydrates and proteins? 50. Triglycerides are an important component of VLDL and chylomicrons. which two lipid transporter proteins? 51. What happens after fatty acids from triglycerides are absorbed in the intestine? They enter the cells that make up the intestinal lining, where they are rebuilt and packaged with cholesterol and proteins to form chylomicrons. 52. Where do the chlyomicrons go? They are collected by the lymph system (lacteals in the intestinal villi), which transport them to the thoracic lymph duct, and are dumped into the subclavian vein to be mixed into the blood. 53. Once chlyomicrons are in the blood, where do they go? 54. What two cells can synthesize and store triglycerides? 55. When glucose levels are low, what does the body require as an energy source? Various tissues can capture the chylomicrons, releasing the triglycerides to be used as a source of energy when glucose is not available. Fat and liver cells fatty acids

4 56. What hormone signals the liver to break glycogen down into glucose and if that is not enough glucose, it will start gluconeogenesis? 57. What enzymes are involved in gluconeogenesis? glucagon 1) Lipase, which breaks down triglycerides to release free fatty acids, and 2) proteases to break down proteins into amino acids. The fatty acids and amino acids are then combined to make new glucose. 58. What hormone signals the production of lipase? glucagon 59. When glucose levels are low, can the brain No. The brain can only use glucose utilize fatty acids as an energy source? 60. How can the brain get more glucose when there the glycerol component of triglycerides can be is not enough? converted into glucose by way of glycogenolysis. 61. Do triglycerides cause heart disease? Probably not, but high levels are present in people with heart disease. 62. What percentage of your diet being from 60% carbohydrates will increase your blood triglyceride levels, especially if you have diabetes or are overweight? 63. When a high carbohydrate diet causes high levels of triglycerides in the blood, what is the condition is called? 64. What does carbohydrate-induced hypertriglyceridemia do to a person s glycemic index? What does that do to insulin levels? 65. What is the function of insulin? 66. What happens when cells are resistant to insulin? 67. What is the best food to reduce triglyceride levels? 68. What does it mean that Omega 3 fatty acids are essential? 69. What are some good things about Omega 3 fatty acids? carbohydrate-induced hypertriglyceridemia Elevates it, causing an overproduction of insulin 70. What is the best source of Omega 3 fatty acids? Flax (linseed) and its oil 71. Why should you avoid Omega-3 fatty acids from fish oil, even though they are heavily advertised? It pulls glucose into the cells. If a cell is insulin resistant, the glucose will stay in the blood and spill into the urine. High levels of blood sugar will damage the brain and blood vessel lining. Up to 3 grams a day of omega-3 fatty acids from flax seed oil (linseed oil). They are not made in our body, so they are needed in our diet. They are essential to normal growth in young children. In adults, they may improve rheumatoid arthritis, cardiovascular disease, and cancer. Because fish oils are too high in vitamin A, which is toxic in high levels. 72. What is the glycemic index? a measure of the effects of carbohydrates on blood sugar levels. 73. What makes a particular carbohydrate have a high glycemic index? What is an example of one? Carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream. Simple sugar like glucose is an example.

5 74. What is an example of a carbohydrate with a Starch low glycemic index? 75. What carbohydrates have slower rates of Foods with a lower glycemic index digestion and absorption, causing a lower insulin demand, and are thus better for a diabetic? 76. What is the Body Mass Index (BMI)? An estimate of body fat 77. What two things are used to calculate BMI? Weight and height 78. Does BMI actually measure the percentage of No you would have to weigh yourself in a body fat? swimming pool to calculate that. 79. What is the quickest, most readily available Glucose source of energy for the body? 80. What are carbohydrates broken down into? Glucose 81. What is broken down if there is not enough blood glucose between meals? Triglycerides are broken down into fatty acids and proteins (including heart muscle) are broken down to amino acids, which combined and made into new glucose 82. What are simple carbohydrates? sugars 83. What are examples of simple carbohydrates? ice cream, cakes, and cookies. Plain white sugar from a box (called refined sugar) 84. Why are sugars called empty calories? because they contribute to energy needs and weight gain without supplying any other nutritional requirements. 85. What are examples of complex carbohydrates? whole grain pasta, rice, bread, and cereal. Less desirable complex carbohydrates (not good for overweight people) are potatoes and corn 86. Name some foods rich in protein red meat, fish, poultry, dairy products, legumes (i.e., peas and beans), nuts, and cereals 87. What happens to proteins that you eat? They are broken down into amino acids and turned into tissues like muscles, skin, hair, and nails. It s also used to make proteins such as hemoglobin, plasma proteins, enzymes, and hormones. 88. How many amino acids are used to make all the 23 proteins in our body? 89. What are essential amino acids? 90. How many are there? There are 9 amino acids which are called essential required from the diet in adults because the body is unable to produce them. Meat 91. What food contains all 23 types of amino acids? 92. What happens if one amino acid is missing The other 22 might not work right. from the diet? 93. What combination of food provides all the Cereal with milk and rice with beans or peas essential amino acids? 94. Are amino acids stored in the body? No, a daily supply is needed. 95. How much meat does a person need per day? Two servings (the size of a deck of cards)

6 96. Which meats are high in protein but also high Red meat (can be 42% fat) in fat? 97. What protein sources are low in fat? protein from plant origins (whole-grain cereals, dark breads, and legumes) 98. Why are protein and amino acid supplements They are not digested as well not good? They can cause you to have an excess of one amino 99. What happens if you have an excess of just one amino acid? 100. What type of fats raise LDL (bad) cholesterol? Name 2 examples 101. What type of fats lower LDL (bad) cholesterol? Name 2 examples acid or another It competes for receptor sites in the small intestine, causing a deficiency in absorption of the other amino acids. Saturated fats; they are solid at room temperature and have an animal origin. Butter and margarine polyunsaturated fats; they are liquid at room temperature and have a plant origin. olive oil, canola oil, corn oil, and safflower oil What are two plant oils that are NOT good, partially hydrogenated palm and coconut oil because they contain saturated fats? 103. Which meats are lower in saturated fats? Turkey, fish, and chicken How many calories are in one pound of fat? 3, How many days will it take to lose one pound 7 days of fat if you eat 500 calories less per day? 106. What is the reason why some people lose more Water loss. It will come back. than that? 107. What are the two general function of vitamins? They are needed for metabolism They make a lot of the body s enzymes What is an enzyme? It breaks a larger molecule down into smaller ones How many vitamins are there, and what are 13 vitamins; fat soluble and water soluble their 2 categories? 110. What are the 4 fat-soluble vitamins? A, D, E, K 111. What happens to excess fat-soluble vitamins? They are stored in fat and liver, and can accumulate to a toxic level 112. What happens to excess water-soluble vitamins? 113. Where is the fat on a fetus? What happens if the mother takes too much vitamin A, D, E, or K? They are excreted in the urine. That is okay as long as you are well hydrated. If not, they can cause kidney damage. In the myelin sheaths (white matter). Excess vitamins can lodge there and disrupt action potentials. The corpus callosum is a large area of white matter in the brain. Dysfunction causes autism Where is vitamin C found? Citrus fruits (oranges, tangerines, lemons) 115. Where is vitamin D made? In the skin after UV light exposure What does vitamin D do? Helps the intestines absorb ingested calcium 117. Lack of vitamin D leads to what disorder in Rickets children? 118. What is a free radical? As a cell is functioning, it generates molecules that have an extra electron, which is called a free radical.

7 119. What is the damage caused by free radicals? free radicals want to run around and get rid of their extra electron (that is called oxidizing the recipient molecule), but none of the other molecules want one, either. The parts of a cell that usually get stuck with a free radical include DNA, proteins, enzymes, and cell membranes. This leads to damage there, and can even lead to cancer What substances deactivate free radicals? What Anti-oxidants are examples? Vitamin C. E, and A, found in fruits and vegetables 121. How many servings of fruits and vegetables 5 servings (2 fruit, 3 vegetables). A serving is about should you eat per day? 122. Is it just as good to take a vitamin pill instead of eating fruits and vegetables? one cup No, you don t get the fiber, which is needed to prevent colon cancer. Also, excess vitamins A, D, E, K are toxic 123. What are some minerals? Calcium, phosphorous, iodine, sodium, chloride, magnesium, potassium, zinc, copper, iron 124. What is calcium used for? bones, teeth, nerve conduction, and muscle contraction. It helps prevent osteoporosis if you have enough calcium and you also exercise What foods are high in calcium? Dairy products and green leafy vegetables 126. What is phosphorus used for? It is used as an energy molecule. It is part of ATP 127. What is iodine used for? Thyroid hormone 128. What are sodium and chloride used for? Regulating water balance 129. How much sodium is needed per day? What 500 mg/day. Excess causes water retention, causing happens if you have too much? high blood pressure 130. What is potassium and sodium used for? Muscle contraction and nerve conduction 131. What are some foods high in potassium? Cantaloupe, avocados, potatoes, beans, bananas, fish, raisins, apricots, dates, and cocoa powder (think chocolate) What is magnesium used for? Helps muscles relax 133. What are some foods high in magnesium? seeds, brans (wheat, rice, and oat), spinach, and cocoa. Any leafy greens have a high amount of magnesium because the center of the chlorophyll molecule is magnesium What is magnesium, zinc, and copper used for? They are critical for most enzymes 135. What is iron used for? To make hemoglobin to transport oxygen in red blood cells 136. How do males and females differ in their iron Females need more, due to loss during menstruation. requirements? If you ingest too much, it makes you constipated What is glucosamine? Where in the body is it an amino sugar and a prominent precursor in the found? synthesis of certain proteins and lipids. It is an important component of joint cartilage 138. How are glucosamine supplements made? Usually from the shells of crustaceans

8 139. Will ingesting glucosamine restore damaged cartilage? No; eating cartilage does not mean you will grow new cartilage. It just breaks down into the same components that are found in cartilage. It may or may not be used to restore cartilage (controversial; no evidence to support it yet). It might prevent cartilage erosion (also controversial) Name three common eating disorders Obesity, bulimia, anorexia nervosa 141. What is obesity? Being about 50 pounds overweight 142. What is moderate obesity? Being about 75 pounds overweight 143. What is morbid obesity? Being 200+ pounds overweight 144. Why is it especially important not to let children become obese? 145. What surgery is for people more than 100 pounds overweight? Their stem cells have not all differentiated yet. If they gain weight, these stem cells will become fat cells, and it will be hard for them to lose weight their whole life. Stomach stapling What are the problems with this surgery? They have to watch their diet to get enough nutrients, they need vitamin B12 shots monthly, and they must not force extra food in, or the stomach will stretch out again What is bulimia? eating to excess (called binge eating) and then purging themselves by some artificial means, such as selfinduced vomiting or use of a laxative What are the dangers of bulimia? causes an abnormal heart rhythm, and damage to the kidneys can even result in death. Vomiting up the food causes the stomach acids to eat away at the pharynx, esophagus, and teeth. Vomiting also causes loss of electrolytes, which can be deadly 149. What is anorexia? 150. What is anorexia nervosa? Anorexia is just not eating. The person might just be sick or recovering from surgery. Anorexia nervosa is a refusal to eat because they think they are too fat. It is often a control issue. The person feels like they do not have control in their life, so they control the food Who is especially at danger for anorexia Athletes such as distance runners, wrestlers, and nervosa? dancers 152. What are some symptoms of starvation? low blood pressure, irregular heartbeat, constipation, being cold, and they tend to get stress fractures. Menstruation ceases in females