1. what is phenylketonuria (PKU)?
genetically inherited disease that is homozygous recessive in genes, there is no enzyme produced to break down phenylalanine into tyrosine
2. people who are homozygous dominant are (PKU)?
3. people who are heterozygous people (PKU)?
not a carrier, asymptomatic
4. homozygous recessive people are (PKU)?
5. if someone has PKU what does this mean?
they lack the enzyme that converts phenylalanine to tyrosine which causes a phenylalanine build up in the blood, it crosses the blood brain barrier and can cause toxicity in the brain 6. what is a lipid?
a family of compounds characterized by their solubility in water
7. what are the three main types of lipids?
triglycerides, phospholipids, and sterols
8. triglycerides make up how much of our diet?
9. what are fats?
lipids that are solid at room temperature
10. what are oils?
lipids that are liquid at room temperature
11. what is the main type of phospholipid?
12. what is main type of sterol?
13. fat provides energy for what?
14. what is the chief form of stored energy?
15. fat is a major component of what?
16. fat protects internal organs from what?
trauma and shock
17. fat provides raw materials for what?
synthesis of many compounds
18. fatt acids are what kind of compound and are composed of what?
organic compounds composed of carbon chains with hydrogen attached
19. what two groups are attached to either ends of the carbon chain?
carboxyl (COOH) and methyl (CH3)
20. what kind of bonds do saturated fatty acids have?
single carbon bonds NOT DOUBLE
21. stearic acid means what about the nomenclature of the fat?
it has 18 carbons and 0 double bonds
22. oleic acid means what about the nomenclature of the fat?
it has 18 carbons and 1 double bond
23. linoleic acid means what about the nomenclature of the fat?
it has 18 carbons and 2 double bonds We also discuss several other topics like usdblackboard
24. linolenic acid means what about the nomenclature of the fat?
it has 18 carbons and 3 carbon bonds
25. using omega nomenclature means what?
you are identifying the position of the carbon double bond relative to the methyl end of the fatty acid
26. the omega carbon is which carbon?
the carbon in the methyl group at one end of the fatty acid
27. a polyunsaturated fatty acid with its first double bond three carbons away from the omega carbon is a what?
an omega3 fatty acid
28. why do fatty acid chains always have an even number of carbons?
when fatty acids hydrolyze they break into chunks of two carbons each with one alpha and one beta carbon so they must have an equal number
29. long chain fatty acids have an estimated range of how many carbons? 1224 carbons
30. what are examples of long chain fatty acids?
meat, fish, and olive oil
31. medium chain fatty acids have an estimated range of how many carbons? 610 carbons
32. what are examples of medium chain fatty acids?
cocoa butter and palm oil
33. short chain fatty acids have an estimated range of how many carbons? <6 carbons
34. what are examples of short chain fatty acids?
35. what is distinct about saturated fatty acids?
they are fully loaded with hydrogen and they have no carbon double bonds If you want to learn more check out how is or isn’t it a social tragedy?
36. examples of saturated fats are?
butter, lard, palm and coconut oils
37. what is distinct about polyunsaturated fats?
there are two or more carbon bonds
38. examples of polyunsaturated fats are?
39. what is distinct about monounsaturated fats?
they have one carbon double bond, the double bond is the point of unsaturation 40. what are examples of monounsaturated fats?
olive oil, canola oil, peanuts and peanut oils
41. the two polyunsaturated fats are what?
linoleic acid and linolenic acid
42. what percent of lipids in the body are triglycerides?
43. to make oil more stable what is added?
44. which fat spoils the fastest?
polyunsaturated fatty acids
45. which fats are more resistant to oxidation/rancidity?
saturated fatty acids
46. what is hydrogenation?
a chemical process by which hydrogens are added to monounsaturated or polyunsaturated fatty acids to reduce the number of double bonds which makes the fat more solid and have a longer shelf life If you want to learn more check out uga geography building
47. hydrogenation produces more of what?
more trans fats which increases the risk of cardiovascular disease
48. phospholipids consist of?
a glycerol backbone, two fatty acids, one phosphate group, and one nitrogen containing compound
49. the fatty acid end of the phospholipid is what?
fat soluble (hydrophobic)
50. the phosphate group end of the phospholipid is what?
51. why are phospholipids good emulsifying agents?
since they have one water soluble end and one fat soluble end they help dissolve fats into watery medium
52. what foods are phospholipids naturally found in?
egg yolk, peanuts, wheat germ, liver, and soybeans
53. what kind of compounds are sterols?
compounds with a multiring structure
54. what are some examples of sterols?
cholesterol, bile, vitamin D, sex hormones, and adrenal hormones
55. when cholesterol is said to be exogenous what is this referring to?
the cholesterol we ingest
56. when cholesterol is said to be endogenous what is this referring to?
the cholesterol we manufacture
57. what are the two essential fatty acids?
linoleic acid and linolenic acid
58. linolenic acid is what kind of omega
59. linoleic acid is what kind of omega?
omega6 If you want to learn more check out choanoflagellates symmetry
60. what is desaturation?
addition of double bonds to essential fatty acids which can result in the production of non essential fatty acids If you want to learn more check out chapter 5 interpersonal communication
61. what is elongation?
lengthening of the carbon chain by two carbons (beta carbon and alpha carbon) 62. 3% of our daily energy intake must be made up of what? If you want to learn more check out ewu net storage
essential fatty acids
63. who is at risk for essential fatty acid deficiencies?
premature infants, young children fed fatfree milk or with low fat diets
64. what is the major site of lipid digestion/hydrolysis?
65. during the digestion process of triglycerides to monoglycerides what happens in the mouth? hard fats melt in the mouth and lingual lipase is secreted to break down
66. during the digestion process of triglycerides to monoglycerides what happens in the stomach?
gastric lipase is secreted, only a small amount of fat digestion happens in the stomach, muscle contractions make fat into smaller pieces
67. during the digestion process of triglycerides to monoglycerides what happens in the small intestine?
fat triggers CCK release, the gallbladder releases bile, lipase and the pancreas act to digest lipids in the small intestine
68. short chain and medium chain fatty acids are absorbed directly into what? the vascular system
69. long chain fatty acids are absorbed first into what and then where?
first into lymphatic system and then into the vascular system
70. the long chain fatty acids that cannot absorb directly into the vascular system are merged into what?
micelles which are emulsifying fat droplets that contain bile, they then enter the intestinal mucous cells
71. when micelles enter the intestinal cells what happens?
monoglycerides and long chain fatty acids are reassembled into new triglycerides which are packaged with cholesterol and protein into chylomicrons
72. where do chylomicrons go after they are triglycerides?
they are absorbed into the lymphatic system, the thoracic duct located near the heart, and then into the vascular system
73. after bile has emulsified fat in the small intestine, it has two destinations? it can be reabsorbed from the jejunum in the small intestine into the vascular system and then recycled back through the liver or it can be trapped by soluble fiber in the large intestine and excreted from the body
74. the process of recycling bile is called what?
75. what are lipoproteins?
clusters of lipids and proteins that serve as transport vehicles for fats in the lymphatic and vascular systems
76. what are the 4 lipoproteins?
chylomicrons, very low density lipoproteins, low density lipoproteins, and high density lipoproteins
77. what is function of chylomicrons?
to transport dietary lipids from intestinal cells to the rest of the body
78. where are chylomicrons made?
within intestinal cells
79. where are very low density lipoproteins made?
in the liver
80. what is the function of very low density lipoproteins?
to transport lipids to various tissues in the body
81. what is the function of low density lipoproteins?
to circulate cholesterol through the body
82. low density lipoproteins correlate to cardiovascular disease how?
they are the less healthy form of cholesterol which increases the risk of cardiovascular disease 83. how dense are chylomicrons?
they are the least dense but the largest
84. how dense are high density lipoproteins?
they are the most dense but the smallest and richest in protein
85. what is the function of high density lipoproteins?
to transport cholesterol from cells back to the liver for excretion
86. why are high density lipoproteins healthy?
because they provide the only way to drain the body of cholesterol, keep cholesterol levels low 87. what are the body's primary energy sources?
triglycerides in food and body fat
88. what does lipoprotein lipase do?
hydrolyzes triglycerides into glycerol
89. inside adipose tissue, what are condensed to triglycerides?
glycerol, FFA's, and monoglycerides
90. true or false, the body can store unlimited amounts of fat if given excesses? true
91. true or false, Lipoprotein Lipase is also required for adipose cells to store fat? true
92. lipoprotein lipase is required for adipose cells to what?
93. after a meal what do adipose cells do?
store fat when triglyceride rich chylomicrons and very low density lipoproteins pass by 94. at rest, how much energy does fat supply?
95. when the body is in a fed state and cells need energy, what enzyme is secreted from adipose cells?
hormone sensitive lipase within adipose cells hydrolyzes triglycerides in fat cells 96. a person who drinks water only (fasts) will metabolize fat at a rapid or slow rate? rapid
97. 1 pound of body fat is equal to how many kcals?
98. if a fasting person expends 1750 kcals/day will they lose 1/2 pound of body fat/day? No, the central nervous system (brain and spinal cord) and the red blood cells require glucose as a fuel
99. how much energy needs to go to the brain, central nervous system, and red blood cells? 1/3
100. how much protein can be broken down to glucose?
101. how much fat can be broken down to glucose?
102. what are formed when fat is metabolized for energy?
103. in a prolonged fast, the brain and nerve cells derive how much of their energy from ketone bodies?
104. during a fast, after glycogen stores are depleted, the body will do what? breakdown both body fat and body protein to provide glucose for energy
105. true or false, humans have extreme amounts of excess protein false
106. during conditions of forced starvation, what kind of person will live the longest? a person with more body fat
107. why is having elevated cholesterol a bad thing?
it is a major cardiovascular disease risk
108. where does dietary cholesterol originate?
109. what does dietary cholesterol do to the risk of CVD?
increases the risk but not as high as saturated fats and trans fats
110. saturated fats raise ______ and increase risk of cvd?
low density lipoproteins
111. trans fats raise ________ and increase the risk of cvd?
low density lipoproteins
112. replacing saturated fats and trans fats with what decreases the risk of cvd? monounsaturated fats
113. replacing saturated and trans fats with what lowers cholesterol? polyunsaturated fatty acids
114. replacing saturated fats and trans fats with what reduces the cvd risk but increases cancer risk?
polyunsaturated fatty acids
115. increasing consumption of omega3 fats does what?
decreases cardiovascular risk, helps prevent blood clots, lowers blood pressure 116. there is some association between fat and which kind of cancer? prostate cancer
117. fat contributes more than how many kcals as carbs and proteins do? more than 2X
118. what is used to replace fats in foods and lower the amount of kcals? carbohydrates/proteins
119. what is an example (talked about in class) of an artificial fat? olestra
120. what is olestra made of?
sucrose and fatty acids
121. how does olestra pass through the GI tract?
undigested because humans lack the enzyme to break down olestra
122. FDA approved olestra for what only?
snack foods because they are not essential foods
123. olestra has what side effects?
abdominal distress and loose stools