22-28 lectures Flashcards

1
Q

what is the first law of thermodynamics?

A

the total energy within a system is constant.
energy cant b created nor destroyed.
energy can only be converted

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2
Q

what complex compounds does food have?

A

lipids and proteins

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3
Q

what does the breaking down of these complex compounds produce alot of?

A

heat

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4
Q

what is anabolism?

A

uses ATP to do cellular work
turns ATP into ADP and Pi
this releases a large amount of energy that is used throughout the body

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5
Q

what is catabolism?

A

the breaking of food and forming a high energy compound such as ATP that can be used through anabolism

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6
Q

what are the 2 manners that the body can work in?

A

aerobic
anaerobic

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7
Q

what pathway drives most of the other metabolic processes?

A

the gycolysis pathway

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8
Q

what process is used in aerobic conditions?

A

oxidation phosphorylation

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9
Q

what does the oxidation phosphorylation do?

A

helps produce lactic acid that can be used to oxidise to form ATP to used during aerobic tasks

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10
Q

what compounds are oxidised in food to form ATP?

A

carbon compounds

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11
Q

what does E intake =?

A

E expended + E stored

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12
Q

what does E stored lead to?

A

weight gain

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13
Q

how is weight gained?

A

if there is a higher energy intake than energy expended so it is stored

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14
Q

how do we lose weight?

A

expend more energy than we are intaking so we have to use the energy that is stored

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15
Q

what is leptin?

A

a signal peptide

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16
Q

what does leptin do?

A

sends a signal to the brain when there is enough energy that is being stored so we can be full

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17
Q

what is J?

A

joule

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18
Q

what are joules?

A

energy required to push against 1 newton of force for 1 meter

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19
Q

what does 1 cal equal?

A

4.184J

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20
Q

what does 1 Cal equal?

A

4.184kJ

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21
Q

how do we measure the energy is food?

A

a calorimetry

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22
Q

what does a calorimetry do?

A

the combustion process in a controlled enviroment to see the released of energy from the food through experiments

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23
Q

what varies the consumption of oxygen?

A

relation to the intensity of the activity and can be used to determine the amount of energy intake that is required

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24
Q

what is indirect calorimetry?

A

the respiratory exchange ratio

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25
Q

what does the indirect calorimetry tell us?

A

the carbondioxide produced over the oxygen consumed which can tell us the metabolic rate of an individual

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26
Q

what is the RER?

A

the respiratory exchange ratio

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27
Q

what increases basal metabolism?

A

athletic training
late stage pregnancy
fever
drugs such as caffiene
hyperthyroidism

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28
Q

what decreases basal metabolism?

A

malnutrition
sleep
drugs such as B-blockers
hypothyroidism

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29
Q

what are the main macronutrients that contribute to energy production?

A

carbohydrates
proteins
fats

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30
Q

what does carbohydrate breakdown into?

A

monosaccarides

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31
Q

what does proteins breakdown into?

A

amino acids

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32
Q

what does nucleic acids breakdown into?

A

nucleotides

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33
Q

what does fats breakdown into?

A

FFAs, MAG, cholesterol

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34
Q

what is the gastrointestinal tract sometimes reffered to as?

A

elemertary tract

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35
Q

what body parts have digestive purposes to contribute to energy production?

A

the liver, pancreas, and the gallbladder

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36
Q

what does saliva do?

A

contains mucus and amylase which starts the digestion of carbhydrates

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37
Q

what happens with pepsin?

A

secreted into the stomach as pepsinogen as the inactive form

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38
Q

what enzymes are secreted by the pancreas?

A

digestive enzymes such as amylase, lipase and several proteases

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39
Q

what does the liver synthesis?

A

bile salts/acid which was important for fat digestion

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40
Q

what are the 2 main phases of digestion?

A

hydrolysis and absorbtion

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41
Q

what hydrolysises proteins?

A

proteases

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42
Q

what is amylopectin?

A

the main component of plant starch and is a large complex structure
need a specific enzyme to hydrolyse these

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43
Q

what is maltose?

A

present in honey
simple structure of 2 glucose monosaccarides to make a disaccaride

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44
Q

what are cellobiase and lactose …. pf eachother?

A

sterioisomers

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45
Q

what is cellobiase?

A

a repeating disaccharide unit in cellulose and is the type of arrangment of functional groups will make it look like there is a different yet it has the same chemical compound

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46
Q

what is sucrose?

A

a disaccaride made up of the monosaccarides fructose and glucose

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47
Q

what can fructose cause?

A

craving for calories to consume more and more materials

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48
Q

what does starch from plants consist of?

A

amylase and amylopectin

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49
Q

what is amylase?

A

a linear polymer of alpha (1-4) linked glucose units

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50
Q

where are the 1-4 glycogenic bonds located?

A

between the 1 and 4 carbon groups

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51
Q

what is amylopectin?

A

a branched polymer of alpha (1-4) and alpha (1-6) linked glucose units

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52
Q

what happens in starch digestion?

A

when enzyme amylase hydrolysises the glycocidic bonds into fragments
the fragments are hydrolysised further until we get small enough to be absorbed into the body

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53
Q

what happens in the final digestion of starch?

A

happens at the brus border where the intestinal epithelial cells produce maltose

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54
Q

how many enzymes are required to hydrolysise the different disaccarides an why are they different?

A

2
because of where the linkage and the arrangments of the disaccarides

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55
Q

what is Kwashiorkor?

A

the presentation where diets can be difficient in proteins which has a lack of amino acids and can have a range of effects on the human body

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56
Q

what does the lack of proteins in the body do?

A

causes an osmotic imbalance in the gastrointestinal system causing the abdomen to swell due to the retention of water
also leads to the level of albumin being low

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57
Q

are proteases active or inactive?

A

inactive

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58
Q

what activates the proteases?

A

cleavage of peptides from there structure

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59
Q

what differs the structure of the amino acids?

A

the side chains

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60
Q

what are the 2 stages of protien digestion that occurs?

A

endopeptidase
exopeptidase

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61
Q

what does endopeptidase do?

A

attacks the peptide bonds within the protein polymer

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62
Q

what does exopeptidase do?

A

attacks the peptide bonds at the end of protein polymer

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63
Q

what are the 2 ways that pepsinogen?

A

-introduced to acid
-pepsin can hydrolysis the unactive pepsinogen to fold and become active

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64
Q

what is the pathway to activate proteases?

A

additional proteases hydrolyses tripsinogen which can hydrolyses chymotrysinogen and procarboxypeptidase to all become active in the pancreas

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65
Q

what is TAG?

A

triacylglycerol

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66
Q

what is triacylglycerol?

A

a cholesterol ester with high amoiunts of fatty acids that promotes the shape of the molecule

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67
Q

what are lipid fats?

A

hydrophobic
so they dont mix with liquids

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68
Q

what is used to help digest lipid fats?

A

bile salts from cholesterol which are stored in the gall bladder

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69
Q

what properties does bile salts have?

A

hydrophobis and hydrophillic which are used to breakdown lipid molecules

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70
Q

what is bilerubin?

A

a breakdown product of haem and gives bile its colour

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71
Q

what does bile contain?

A

water, bile acids, electrolytes, phospholipids, cholesterol, bile pigments

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72
Q

where is bile salts synthesized and stored?

A

it is synthesized in the liver and stored in the gall bladder

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73
Q

what do polypeptide hormones create?

A

a signal t help stimulate the food that has been intaken and is being digested

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74
Q

what is lipid enzymes used for?

A

the breakdown of lipid components of the food that has been taken up

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75
Q

what is the pancreatic lipase enzyme?

A

used to bind to the lipase and enhances the activate to hydrolysis the monoacylglycerol

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76
Q

what is the hydrolysis of the monoacylglycerol important for?

A

getting fats into the body so it can be utilized

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77
Q

what do bile salts do?

A

arrange to form michelles type structures that stabilize the triacylglycerol and are then absorbed across the membrane

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78
Q

what is absorbance dependant on?

A

efficiency of the GI tract

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79
Q

what maximises the surface of the GI tract?

A

the villi and microvilli

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80
Q

what does fat malabsorbtion lead to?

A

excess of fat and fat soluable vitamins in faeces
this causes a condition that interfers with bile or pancreatic lipase secretions

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81
Q

what is xenical?

A

a potent inhibitor of pancreatic lipase
its a mode of action to make covalent interaction with the enzyme and blocks the function of the lipase

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82
Q

what structures does fat go into after it has crossed the plasma membrane?

A

chylomicrons

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83
Q

what do chylomicrons do?

A

move fat into the lymph and overall getting it into the blood stream

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84
Q

what are lipoproteins?

A

complexes that have evolved to stabilize lipids for transporting in the blood to tissues

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85
Q

what are proteins that have many functions?

A

apoproteins

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86
Q

what are some of the functions of apoproteins?

A

structural assembly, ligands for cell surface receptors and enzyme cofactors for lipoprotein lipase

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87
Q

what are the 4 main classes of lipoproteins?

A

chylomicrons, very low density, low density, high density

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88
Q

what is VLDL?

A

very low density lipoproteins

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89
Q

what is LDL?

A

low density lipoproteins

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90
Q

what is HDL?

A

high density lipoproteins

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91
Q

what is needed to make a chemical sequence for TAG synthesis?

A

co-enzyme A to activate them so that the metabolism can be achieved

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92
Q

what is CoA synthesised from?

A

pantothenate, ATP and cystine

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93
Q

what is CoA?

A

co-enzyme A

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94
Q

what is the lowest lipoprotein?

A

chylo because they have alot of TAG compared to the amount of protein

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95
Q

how can we tell the lipoprotein composition?

A

in clinical plasma samples to be analysed by native gel electrophoresis

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96
Q

what do labs measure in lipoproteins?

A

total cholesterol, HDL, triglycerides-used to identify dyslipidemia

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97
Q

how can we estimate the LDL?

A

total cholesterol - HDL - triglycerides

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98
Q

what are the 2 major lipid transport pathways?

A

exogenous
endogenous

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99
Q

what is the exogenous pathway?

A

shipping around the body

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100
Q

what is the endogenous pathway

A

dealing with lipid molecules such as storing in tissues for energy production functions

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101
Q

where do chylomicrons return to?

A

the liver to be used again

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102
Q

what is the liver important for?

A

lipid transformation and the process of storing and using fats

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103
Q

where is the lipoprotein lipase found?

A

endothelial surface of capillaries

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104
Q

what does lipoprotein lipase do?

A

hydrolysises TAG in lipoproteins to 2-monoacylglycerol and fatty acids

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105
Q

what activates lipoprotein lipase?

A

apoCII

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106
Q

what can defects in either apoCII or lipoprotein lipase lead to?

A

elevated levels of chylomicrons and plasma triacylglycerol

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107
Q

what is FH?

A

familial hypercholesterolemia

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108
Q

what does FH do?

A

common form of hyperlipidemia which leads to premature athersclerosis

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109
Q

what causes FH?

A

a defect in LDL receptor genes

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110
Q

is LDL good or bad?

A

bad

111
Q

is HDL good or bad?

A

good

112
Q

how can we treat FH?

A

statins to lower LDL and increase HDL

113
Q

why is LDL considered the bad cholesterol?

A

as it has large levels of cholesterol that usually has secondary effects amoung the host that consumed it

114
Q

why can sugar diffuse across cell membranes?

A

they are highly water soluable

115
Q

what does sugar require to diffuse across the cell membrane?

A

a specific transporter protein anchored in the membrane that form pores in the membrane

116
Q

what are the 2 types of transporters?

A

active and facilitated

117
Q

what are active transporters?

A

moving against the concentration gradient that needs energy from ATP to do so

118
Q

what is facilitated transporters?

A

a passage down the concentrtion gradient

119
Q

what is GLUT 2?

A

a facilitated transporter found in the liver, pancreas, kidney and intestinal epithelial

120
Q

what is SGLT 1?

A

a secondary active transporter and is found in intestinal epithelium

121
Q

how does SGLT1 and GLUT 2 work for glucose transport?

A

used to move glucose into the epithelial cell in a glucose/Na+ co-transporter and GLUT 2 is used to move glucose out of a cell

122
Q

what is SGLT 1 used for?

A

move both Na+ and glucose into the cell increasing the concentration of both within the cell

123
Q

what pumps Na+ out of the epithelial call to maintain a low Na+ in the cell?

A

Na+/K+ ATPase

124
Q

what does it mean for SGLT 1 is Na+ is needed to move glucose into the cell?

A

SGLT 1 is an active transporter

125
Q

how many K+ are pumped into a cell for every 3Na+ pumper out via ATPase?

A

2

126
Q

what causes a conformational change to enable the transport of the Na+ followed by K+?

A

hydrolysis of ATP and phosphorylation of the ATPase transporter

127
Q

where does GLUT 4 transport to?

A

glucose into the muscles and adipose tissue

128
Q

where does GLUT 3 transport to?

A

glucose to the brain

129
Q

what is the PepT1 membrane transporter?

A

absorbs di- and tri- peptides in the small intestine by co-transport with H+ ions

130
Q

what does cytoplasmic peptidase do?

A

further digests the di and tri peptides into individual amino acids

131
Q

where do amino acids go once absorbed into the epithelial cell?

A

exported into the blood circulation

132
Q

what does transepithelial transport?

A

absorbed amino acids into the small intestine from the lumen

133
Q

what is transepithelial?

A

semi-specific Na+ dependant transport system

134
Q

what does Na+ dependant transporters transport?

A

both Na+ and amino acids

135
Q

what is lactose intolerant?

A

a lack of lactase

136
Q

what can a lack of lactase do?

A

causes bloating, flatulence and diarrheoa due to fermetation of lactose by intestinal bacteria

137
Q

what does pancreatitis lead to?

A

inappropriate activation of zymogens resulting in self digestion

138
Q

what are stomach ulcers?

A

due to the breakdown of the mucosa which normally protects against protease action

139
Q

what does cystic fibrosis cause?

A

malabsorption

140
Q

what does coeliac disease lead to?

A

malabsorption

141
Q

what happens in cystic fibrosis?

A

it causes mucous secretions which block the pancreatic duct and secretion of pancreatic enzymes

142
Q

how can we avoid cystic fibrosis?

A

taking supplements containing pancreatic enzymes such as pancreatin which is a pancreas extract

143
Q

what is coeliac disease?

A

of the small intestine
body reacts to gluten protien present in wheat
antibodies react with transglutaminase and villi are flattened so nutrient arent absorbed

144
Q

what can coeliac disease lead to?

A

gastrointestinal syptoms

145
Q

what does intestinal endonuclease enzymes do?

A

hydrolyses the phosphodiester bonds linking individual nucleotides

146
Q

what does intestinal exonuclease enzymes do?

A

release individual nucleotides

147
Q

what happens to individual nucleotides?

A

they are absorbed via nucleotide transporters

148
Q

what links individual nucleotides together?

A

phosphodiester bonds in nucleic acid polymers

149
Q

what is beriberi?

A

thymon deficiency

150
Q

what causes beriberi?

A

a lack of vitamins in their diets for example thiamine (vitamin B1) deficiency

151
Q

what can anti-inhibitors of thiamine do?

A

either destroy thiamine in the gut or inhibit the receptors and absorbtion

152
Q

what are vitamins and minerals effective to?

A

co-factors and coenzymes

153
Q

what are vitamins?

A

accessory substances
from food and are needed in the body
they are organic substances which means that they are made by plants and animals

154
Q

why are vitamins hard to test in the lab?

A

they are very fragile and will breakdown in heat or UV

155
Q

what are minerals?

A

inorganic elements that come from soil and water and are absorbed by plants or eaten by animals

156
Q

what is the primary differece between organic and inorganic compounds?

A

organic compounds always contain carbon while inorganic compounds do not contain carbon

157
Q

can we make vitamins in our bodies?

A

no

158
Q

what are the 2 ways that vitamins can be?

A

water-soluable
fat-soluable

159
Q

what is the only vitamin we can make ourselves?

A

vitamin D through our skin from UV rays

160
Q

what are water-soluable vitamins?

A

absorbed by portal blood and is generally excreted in the urine when plasma levels exceed renal threshold
not stored in large quantities in body tissues

161
Q

what are fat-soluable vitamins?

A

enter lymphatic system as part of a chylomicron
they are stored in larger quantites in the body tissue
they can from food with fats in them
they are digested like fats through michelles and absorbed in the small intestine and later absorbed into the blood

162
Q

what tissue stores the fat-soluable vitamins and why?

A

adipose tissue
because they dont excrete as easy as water soluable vitamins

163
Q

which type of vitamins have a higher chance to lead to toxicity?

A

fat-soluable vitamins

164
Q

what is vitamin C?

A

an antioxidant

165
Q

how much of our body weight is mineral?

A

4%

166
Q

what are mineral responsible for?

A

structual functions involving skeleton and soft tissues and regulatiing functions including neuromuscular transmission, blood clotting, oxygen transport and enzymatic activity

167
Q

what are the 2 classes of minerals?

A

major and minor

168
Q

what are major minerals?

A

we eat alot of major minerals
found in a great abundance in the body

169
Q

how many major minerals does an adult need?

A

100mg/d

170
Q

what can a lack of calcium lead to?

A

rickets

171
Q

what is rickets?

A

lack of calcium
softening of the bones in kids only

172
Q

what is osteoporosis?

A

the demineralization within the bones within the body

173
Q

how many minor minerals do we have in our body?

A

100 milligrams

174
Q

what do enzymes do?

A

make reactions works faster as they lower the activation energy

175
Q

how do enzymes lower the activation energy?

A

binding to the substrate at a location on the enzyme called the active site

176
Q

what do enzymes need if they cant catabolise a reaction by themselves?

A

they need the help of co-enzymes and co-factors to function properly

177
Q

what are co-enzymes?

A

organic carrier molecules
they are involved in transferring things from one molecule to another

178
Q

where are many vitamins derrived from?

A

vitamins

179
Q

what are co-factors?

A

the general term for small molecules required for the activity of their associated enzyme
these dont transfer things but are more likely to stabilize or are used to convert substrate into products

180
Q

what does DNA polymerase enzymes do?

A

helping with DNA synthesis
uses positive charge Mg ion as a co factor to stabilize the negative charge

181
Q

why are DNA very negatively charged?

A

due to the negatively charged phosphate groups

182
Q

what is thiamine a coenzyme for?

A

forming thiamine pyrophosphate in a variety of metabolic processes
plays a role in ATP production and nucleic acid which is used in DNA and RNA synthesis

183
Q

what is TPP?

A

thiamine pyrophosphate

184
Q

what can a lack of thiamine lead to?

A

negative impacts on the energy production and nutrient metabolism which can be life threatening

185
Q

what does thiamine consist of?

A

an aminopyrimidine ring linked to a thiazole ring by a methylene bridge

186
Q

what turns thiamine into TPP?

A

2 phosphate groups added an

187
Q

where can thiamine be found in?

A

seeds, beans, pork, spinach, cornflour and breakfast cereals

188
Q

what can cause thiamine deficicnecy?

A

insufficient intake in the diet can be caused by low absorbtion or high excretion rates than normal which can be due to alcohol dependance, HIV/AIDS, medication

189
Q

who is most likely to have thiamine deficiency?

A

alcoholics

190
Q

what are some symptoms of thiamine deficiency?

A

weight loss, anorexia, confusion, muscle weakness and cardiovascular symptoms

191
Q

what is ATF?

A

anti-thiamine factors

192
Q

what does ATF do to thiamine?

A

reacts with thiamine to form an oxidised, inactive product

193
Q

what is the currency of the cell?

A

ATP

194
Q

what makes ATP the main currency of energy?

A

the high energy bonds as the phosphate is removed and the energy is released

195
Q

where does the energy to bond the phosphates back onto the ADP?

A

the oxidation of fats and glucose makes a small amount of energy

196
Q

what is delta G?

A

Gibbs free energy

197
Q

what can the gibbs free energy tell us?

A

the relative abundance of the substrates and products, and the enrgy stored in the chemical bonds of the products and substrates

198
Q

what happens if delta G is less than 0 for A to B?

A

reaction is spontaneous, energy is released, it is energetically favouable

199
Q

what happens if delta G is equal to 0 for A to B?

A

reaction is at equalibrium, and there is no change in energy

200
Q

what happens is delta G is greater than 0 for A to B?

A

reaction is not spontaneous, energy is released, it is energetically unfavourable

201
Q

what is the favourable reaction of ATP?

A

the breaking of the phosphate group and releasoing energy

202
Q

what is the delta g of the ATP hydrolysis?

A

-30kJ/mol

203
Q

what i the delta G of ATP synthesis?

A

30kJ/mol

204
Q

what is delta G o?

A

delta G under standard conditions at pH of 7

205
Q

what does 1 mol of protons pH?

A

pH 0

206
Q

what is it if the delta G is negative after adding 2 delta Gs from two reactions together?

A

the reaction is energetically favourable and the coupled reaction can happen

207
Q

what is it if the delta G is positive after adding 2 delta Gs from two reactions together?

A

the reaction is energetically unfavourable and the coupled reaction will not work

208
Q

what happens in redox reactions?

A

one molecule is oxidised and loses an electron and the other is reduced as it accepts the electron from the other

209
Q

what is the reducing reagent in a redox reaction?

A

the molecule that is oxidised

210
Q

what is the oxidising agent of a redox reaction?

A

the molecule that is reduced

211
Q

what do biological redox reactions often involve?

A

the transfer of hydrogen atoms

212
Q

in the oxidation of sugar, where is energy captured to synthesis ATP?

A

at each little step of the reaction process

213
Q

what are the enzyemes that catalyse redox reactions in biologiocal conditions?

A

dehydrogenases

214
Q

what helps the energy released in feul molecules?

A

oxidation reactions

215
Q

what is NAD?

A

nicotinamide adenine dinucleotide

216
Q

what is NAD derrived from?

A

niacin (vitamin B3)

217
Q

what does NAD do?

A

its a co-enzyme that accepts a hydrogen and an electron in metabolic pathways
it undergoes a 2-electron reduction reaction

218
Q

what does NAD pick up in a 2-electron reaction?

A

a proton and an electron to become NADH

219
Q

what is FAD?

A

flavin adenine dinucleotide

220
Q

what is FAD derrived from?

A

riboflavin (vitamin B2)

221
Q

what does FAD do?

A

accepts 2 hydrogens in pathways

222
Q

what are flavin coenzymes doing?

A

tightly bound to the proteins with which they interact

223
Q

what is CoA derrived from?

A

pantothenic acid (vitamin B5)

224
Q

what does CoA carry?

A

no electrons but they carry aycl groups (chains of carbon)

225
Q

what are the 2 forms of CoA?

A

free co-enzyme
acyl group attached

226
Q

what is the process that oxidises glucose?

A

glycolysis

227
Q

where does gylcoilysis occur?

A

in the cytoplasm within eukaryotes, everything else happens in the mitochondria

228
Q

what cells can use glucose as energy?

A

every cell

229
Q

what is an essential fuel for RBCs?

A

glucose

230
Q

why does RBCs rely on glucose?

A

because they dont have mitochondria so they dont have any other pathways
but they do have cytoplasm so they are able to oxidise glycolysis

231
Q

why is glucose the perferred feul of the brain?

A

as it is high energy requirements as the brain has to fire alot of action potentials
glucose can get across the blood brain barrier and fatty acids cannot

232
Q

why is glucoswe the favoured feul of the eyes?

A

as there is not many blood vessels in the eye so it doesnt interfer with light that enters the eye so the eye has mainly cytoplasm

233
Q

why does red muscle cells use fats?

A

as it has alot of mitochondria

234
Q

what are red muscle good for and why?

A

aerobic conditions as the mitochondria need oxygen

235
Q

why does white muscle cells use glucose?

A

no mitochondria so needs no oxygen is needed

236
Q

what is white muscle good for and why?

A

anaerobic conditions as they dont have mitochondria so no oxygen is needed

237
Q

what happens in glycolysois?

A

splitting of glucose
the 6 carbon glucose goes to 2 molecules of 3 carbon pyruvate

238
Q

where is energy conserved in the first stages of glycolysis?

A

in ATP and NADH

239
Q

what are the 2 phases of glycolysis?

A

the investment phase
energy payoff phase

240
Q

what happens in the investment phase of glycolysis?

A

we have to put a little energy into get a molecule into the right form, this activates our glucose

241
Q

what happens in the energy payoff phase of glycolysis?

A

when we produce 4 ATP and the NAD+ goes to 2 NADH as the glucose becomes pyruvate molecules

242
Q

what catalyses the gluose bonding to the phosphate?

A

hexokinase

243
Q

what does hexokinase do?

A

can couple the reaction to the hydrolysis of the ATP and we add the delta G and then the reaction becomes energetically favourable so the reaction can occur

244
Q

what is the delta go of the hexokinase reaction in glycolysis?

A

-16kJ/mol

245
Q

what is the second step of glucose activation?

A

the rearrangment which is a unfavouarbale reaction but the reaction still happens as the opathway is energetically favourable

246
Q

what is the delta G in the second step of glucose activation?

A

+1.6kJ/mol

247
Q

what does G-6-P go to?

A

F-6-P

248
Q

what does phosphofructose do?

A

uses ATP hydrolysis to turn F-6-P into FBP

249
Q

what is the delta G of the phosphofructose reation?

A

-14kJ/mol

250
Q

what does aldolase catalysises?

A

the splitting reaction as it cleaves our molecule and splits it from 1 six carbon and 2 phophates into 2 three carbons and 1 phosphate molecules

251
Q

what are the 2 products made in the splitting reaction?

A

DHAP and G-3-P
G-3-P is used so since DHAP isnt used it becomes a G-3-P to be used

252
Q

what is the ATP synthesis equation?

A

ADP + Pi

253
Q

what is SLP?

A

substrate level phosphorylation

254
Q

what does SLP do?

A

its the direct use of energy from a substrate molecule to drive the synthesis of ATP

255
Q

how do we release the energy to drive the SLP?

A

the clevage of a high energy phosphate ester bond on a substrate so we use ATP

256
Q

what does oxidation of G-3-P do?

A

NAD+ is reduced to NADH and during this a phosphate is then added onto the substrae so now there is 2 high level bonds onto the substrate

257
Q

what does G-3-P go to?

A

BPG

258
Q

what happens to the phosphate from the BPG?

A

chopped off and then added back onto the ATP molecule
this cleavage of the phosphate group releases energy so its energetically favourable

259
Q

what is the delta G when we chop the phosphate off the BPG?

A

-49.3kJ/mol

260
Q

what does BPG go to?

A

3PG

261
Q

what is arsenic poisoning?

A

when there is arsenic in the body and it subsitutes for a phosphate and prevents the reaction from capturing the energy that is released
so there is no net gain of ATP in this glycolysis

262
Q

what is 3PG rearranged into and why?

A

2PG and the PEP
to get the moecule into a form that enables the following reactions

263
Q

what is PEP?

A

a phosphate group cleaved off by pyruvate kinase to make pyruvate

264
Q

what is the delta G of the coupled reaction of 3PG?

A

-31.9kJ/mol

265
Q

what is the overall delta G of the turning glucose into pyruvate?

A

-73.3kJ/mol so the reaction is energetically favourable

266
Q

what is pyruvate converted into to go into the citric cycle?

A

caetyl-CoA

267
Q

where does pyruvate getting converted into acetyl-CoA occur?

A

in the mitochondria matrix

268
Q

what happens to the energy in the pyruvate to acetyl-CoA reaction?

A

NAD+ is reduced to NADH which releases energy and this energy adds CoA to the molecule to then be fed into the citric acid cycle

269
Q

what does the citric acid cycle require?

A

oxygen because its an aerobic oxidation

270
Q

what does fates of pyruvate in anaerobic glycolysis oxidise?

A

NADH to NAD+ and no ATP is getting made to turn pyruvate into lactate

271
Q

what does lactate do to muscles?

A

makes them feel fatigued

272
Q

what does the lactate formation allow?

A

the regeneration of NAD+

273
Q

what does lactate dehydrogenase reaction oxidise?

A

NADH