1D: Principles of Bioenergetics & Fuel Molecule Metabolism Flashcards Preview

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Flashcards in 1D: Principles of Bioenergetics & Fuel Molecule Metabolism Deck (251)
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1
Q

Endothermic Reactions

A

Require energy, nonspontaneous, positive heat flow (absorbed = feels cold), increase enthalpy, breaking chemical bonds

2
Q

Exothermic Reactions

A

Release energy, can be spontaneous, high entropy, negative heat flow (lost = feels hot), decrease enthalpy, form chemical bonds

3
Q

Free Energy Equation

A

dG = dH - TdS

4
Q

Standard Free Energy Equation

A

dG = -RTlnK

5
Q

dG less than 1

A

K>1, favors products, spontaneous

6
Q

dG equal to 0

A

K=1, at equilibrium

7
Q

dG greater than 1

A

K

8
Q

Nonspontaneous Reaction Criteria

A
\+G = +H, -S
\+G = +H, +S (low temp)
\+G = -H, -S (high temp)
9
Q

Spontaneous Reaction Criteria

A
  • G = +H, +S (high temp)
  • G = -H, +S
  • G = -H, -S (low temp)
10
Q

Spontaneous Reaction Criteria

A
  • G = +H, +S (high temp)
  • G = -H, +S
  • G = -H, -S (low temp)
11
Q

ATP Hydrolysis

A

ATP + H2O -> ADP + Pi

Exergonic (dG

12
Q

ATP Group Transfer

A

When ATP is depleted during exercise, phosphate is transferred from phosphocreatine to ADP to replenish ATP

13
Q

Oxidation Half Reaction

A

Loses electrons (uses solid)

14
Q

Reduction Half Reaction

A

Gains electrons (produces solid)

15
Q

Soluble Electron Carriers

A

Electrons transferred from one electron carrier to another; energy level decreases; energy is released

16
Q

Ubiquinone (Q)

A

Lipid-soluble electron carrier; reduced to ubiquinol

17
Q

Cytochrome c

A

Water-soluble electron carrier; contains Fe pigment

18
Q

Quinone

A

Lipid-soluble carrier that shuttles electrons between large macromolecular complexes embedded in the membrane

19
Q

Quinone

A

Lipid-soluble carrier that shuttles electrons between large macromolecular complexes embedded in the membrane

20
Q

Flavoproteins

A

Derivatives of riboflavin; FAD and FMN; involves in bioluminescence, photosynthesis, DNA repair, apoptosis

21
Q

Electron Transfer Flavoprotein

A

Function as a specific electron acceptor for primary dehydrogenases

22
Q

Carbohydrate Formula

A

(CH2O)n; deoxy = hydrogen replacing -OH

23
Q

Aldose

A

Sugar with an aldehyde group

24
Q

Ketose

A

Sugar with a ketone group

25
Q

Pyranose

A

Hexagonal ring

26
Q

Furanose

A

Pentagonal ring

27
Q

Common Sugars

A

Glucose, Galactose, Fructose

28
Q

Absolute Configuration

A

D/L = based on chirality of the carbon atom furthest from the carbonyl group

Alpha/Beta = anomeric configuration

29
Q

Alpha Anomer

A

Oxygens are cis to each other

30
Q

Beta Anomer

A

Oxygens are trans to each other

31
Q

Beta Anomer

A

Oxygens are trans to each other

32
Q

Epimers

A

Diastereomers; different configuration at one of the chiral carbons

33
Q

Anomers

A

Stereoisomers; different configuration at the same carbon

34
Q

Hydrolysis of Glycoside Linkage

A

Done by enzymes (amylase = starch, glycosylase = nucleotide)

35
Q

Hydrolysis of Glycoside Linkage

A

Done by enzymes (amylase = starch, glycosylase = nucleotide)

36
Q

Monosaccharides

A

Colorless, water-soluble, crystalline solid

37
Q

Mutarotation

A

Equilibrium between the alpha and beta anomer

38
Q

Disaccharides

A

Simple polysaccharides, made via condensation reaction between two monosaccharides

39
Q

Maltose

A

Glucose + Glucose (1->4 Linkage)

40
Q

Sucrose

A

Glucose + Fructose (1->2 Linkage)

41
Q

Lactose

A

Galactose + Glucose (1->4 Linkage)

42
Q

Lactose

A

Galactose + Glucose (1->4 Linkage)

43
Q

Polysaccharides

A

Long chains of repeating monosaccharide units connected by glycosidic links; Storage or Structural

44
Q

Storage Polysaccharides

A

Starch and Glycogen

45
Q

Structural Polysaccharides

A

Chitin and Cellulose

46
Q

Starch

A

B 1->4 linkages

47
Q

Cellulose

A

A 1->4 linkages

48
Q

Cellulose

A

A 1->4 linkages

49
Q

Glycolysis

A

Conversion of Glucose into 2 molecules of Pyruvate; produces 4 ATP molecules and 2 NADH; occurs in cytosol

50
Q

Glycolysis Net Products

A

2 NADH 2 ATP

51
Q

Glycolysis Enzymes

A
  1. Hexokinase
  2. Phosphoglucoisomerase
  3. PFK
  4. Aldolase
  5. GAP Dehydrogenase
  6. Phosphoglycerate Kinase
  7. Phosphoglycerate Mutase
  8. Enolase
  9. Pyruvate Kinase
52
Q

Hexokinase

A

Glucose -> G6P

-ATP

53
Q

Phosphoglucoisomerase

A

G6P -> F6P

54
Q

PFK

A

F6P -> F1,6BP

-ATP

55
Q

Aldolase

A

F1,6BP -> GAP or G3P

56
Q

GAP Dehydrogenase (x2)

A

GAP -> 1,3BPG
-Pi
+NADH

57
Q

Phosphoglycerate Kinase (x2)

A

1,3BPG -> 3PG

+ATP

58
Q

Phosphoglycerate Mutase (x2)

A

3PG -> 2PG

59
Q

Enolase (x2)

A

2PG -> PEP

+H2O

60
Q

Pyruvate Kinase (x2)

A

PEP -> Pyruvate

+ATP

61
Q

Glycolytic Feeder Pathways

A

Glycogenolysis, Starch Metabolism

-contribute glucose to the pathway

62
Q

Fermentation

A

Anaerobic Glycolysis; converts sugars to acids, gases or alcohol; occurs in bacteria, yeast and o2 starved muscle cells

63
Q

Fermentation

A

Anaerobic Glycolysis; converts sugars to acids, gases or alcohol; occurs in bacteria, yeast and O2 starved muscle cells; regenerates NAD to keep glycolysis going

64
Q

Fermentation

A

Anaerobic Glycolysis; converts sugars to acids, gases or alcohol; occurs in bacteria, yeast and O2 starved muscle cells; regenerates NAD to keep glycolysis going

65
Q

Fermentation Chemistry

A

Redox reaction, reduces pyruvate to oxidize NADH into NAD; 1 NAD per Pyruvate

66
Q

Alcoholic Fermentation

A

Pyruvate reduced to Ethanol

67
Q

Lactic Acid Fermentation

A

Pyruvate reduced to Lactate

68
Q

Gluconeogenesis

A

Synthesis of Glucose from non-carbohydrate sources (pyruvate, lactate, glycerol); occurs in the liver

69
Q

Gluconeogenesis Unique Enzymes

A

Pyruvate Carboxylase
PEP Carboxykinase
G6Pase

70
Q

Pyruvate Carboxylase

A

Pyruvate -> Oxaloacetate
+HCO3
-ATP

71
Q

PEP Carboxykinase

A

OAA -> PEP

-GTP + CO2

72
Q

G6Pase

A

G6P -> Glucose
+H2O
-Pi

73
Q

G6Pase

A

G6P -> Glucose
+H2O
-Pi

74
Q

F1,6BP

A

Activates PFK,
high levels = glycolysis
low levels = gluconeogenesis

75
Q

PPP Oxidative Phase

A

Generates NADPH

76
Q

PPP Non-oxidative Phase

A

Generates 5C Sugar (Ribose-5-Phosphate)

77
Q

PPP Non-oxidative Phase

A

Generates 5C Sugar (Ribose-5-Phosphate)

78
Q

Net Products of Respiration

A

36 ATP

79
Q

Net Products of Respiration

A

36 ATP

80
Q

Regulation of Metabolic Pathways

A

Done through feedback inhibition, isozymes, enzymes concentrations, rapid effect or slow effects

81
Q

Isozymes

A

Different enzymes that catalyze the same reaction

82
Q

Regulation of Glycolysis

A

Irreversible steps: Hexokinase, PFK, Pyruvate Kinase

F2,6BP, AMP

83
Q

F2,6BP

A

Potent Activator of PFK-1, synthesized when blood sugar is low and glucagon elevates cAMP

84
Q

PEPCK Inhibitors

A

ADP

85
Q

F1,6BP

A

Activates PFK,
high levels = glycolysis
low levels = gluconeogenesis

86
Q

Glycogenolysis [Muscle]

A

Provides G6P for Glycolysis; Muscle lacks G6Pase

87
Q

Glycogenolysis [Liver]

A

Creates free glucose to be released into the bloodstream for cellular uptake

88
Q

Glycogenolysis Enzymes

A

Glycogen Phosphorylase
Phosphoglucomutase
Glycogen Debranching Enzyme

89
Q

FBPase Activators

A

Citrate

90
Q

Glycogenesis Enzymes

A
Hexokinase
Phosphoglucomutase
UDP-Glucose Phosphorylase
Glycogenin
Glycogen Synthase
91
Q

Pyruvate Kinase Activators

A

F1,6BP

92
Q

Glycogenin

A

Acts as a primer, converting glucose to glycogen; it is a glycosyltransferase

93
Q

Pyruvate Carboxylase Activators

A

Acetyl CoA

94
Q

Pyruvate Carboxylase Inhibitors

A

ADP

95
Q

Protein Kinase A

A

Activated by epinephrine through adenylate cyclase activity; activated by calcium ions + cAMP

Inhibits Glycogen Synthase

96
Q

Insulin

A

Stimulates glycolysis, glycogenesis, protein anabolism, lipogenesis

97
Q

Glycogenolysis [Muscle]

A

Provides G6P for Glycolysis; Muscle lacks G6Pase

98
Q

GLUT2

A

Transports dephosphorylated glucose into the bloodstream

99
Q

Metabolic Control Analysis

A

Examines how the control of influx and concentrations of metabolites in a metabolic pathway distributed between different enzymes

100
Q

Acetyl-CoA Production

A

Produced via Pyruvate Dehydrogenase Complex and Pyruvate Formate Lyase

101
Q

Glycogenesis Enzymes

A

Hexokinase
Phosphoglucomutase
UDP-Glucose Phosphorylase
Glycogenin

102
Q

UDP-Glucose Phosphorylase

A

Converts G1P to UDP-Glucose, forming pyrophosphate

103
Q

Glycogenin

A

Acts as a primer, converting glucose to glycogen; it is a glycosyltransferase

104
Q
Dihydrolipoyl Dehydrogenase (E3)
(FAD, NAD+)
A

Restores the complex to its initial state producing NADH

105
Q

Glycogen Phosphorylase

A

Phosphorylation activates; b form -> a form

106
Q

Protein Kinase A

A

Activated by epinephrine through adenylate cyclase activity; activated by calcium ions + cAMP

Inhibits Glycogen Synthesis

107
Q

Citric Acid Cycle Enzymes

A
  1. Citrate Synthase
  2. Aconitase
  3. Isocitrate Dehydrogenase
  4. Alpha-Ketoglutarate Dehydrogenase
  5. Succinyl-CoA Synthetase
  6. Succinic Dehydrogenase
  7. Fumarase
  8. Malate Dehydrogenase
108
Q

Citrate Synthase

A

Acetyl-CoA + Oxaloacetate -> Citrate + CoA

109
Q

GLUT2

A

Transports dephosphorylated glucose into the bloodstream

110
Q

Metabolic Control Analysis

A

Examines how the control of influx and concentrations of metabolites in a metabolic pathway distributed between different enzymes

111
Q

Alpha-Ketoglutarate Dehydrogenase
[NAD]
[CoA]

A

Alpha-Ketoglutarate -> Succinyl-CoA
+NADH
+CO2
+H

112
Q

Acetyl-CoA Formation Reaction

[Pyruvate Dehydrogenase Complex]

A

Pyruvate + CoA + NAD+ –> Acetyl-CoA + NADH + H+ CO2

113
Q
Pyruvate Dehydrogenase (E1)
(Thiamine Pyrophosphate [TPP])
A

Attaches Acetyl Group to Sulfur Atom

114
Q
Dihydrolipoyl Transacetylase (E2)
(Lipoate, CoA)
A

Transfers Acetyl from Sulfur to CoA

115
Q
Dihydrolipoyl Dehydrogenase (E3)
(FAD, NAD+)
A

Restores the complex to its initial state producing NADH

116
Q

Citric Acid Cycle Products [In Order]

A

Acetyl-CoA + Oxaloacetate -> Citrate -> Isocitrate -> Alpha-Ketoglutarate -> Succinyl-CoA -> Succinate -> Fumarate -> Malate -> Oxaloacetate

117
Q

When is GTP Produced in the CAC?

A

From the Succinyl-CoA Dehydrogenase reaction

118
Q

Citric Acid Cycle Enzymes

A
  1. Citrate Synthase
  2. Aconitase
  3. Isocitrate Dehydrogenase
  4. Alpha-Ketoglutarate Dehydrogenase
  5. Succinyl-CoA Synthetase
  6. Succinic Dehydrogenase
  7. Fumarase
  8. Malate Dehydrogenase
119
Q

Regulation of Pyruvate Dehydrogenase

A

Activated by Ca, NAD+, CoA

Inhibited by high levels of Acetyl-CoA, NADH

120
Q

Aconitase

[H2O]

A

Citrate -> Isocitrate

121
Q

Isocitrate Dehydrogenase

[NAD]

A

Isocitrate -> alpha-ketoglutarate
+NADH
+CO2

122
Q

Alpha-Ketoglutarate Dehydrogenase
[NAD]
[CoA]

A

Alpha-Ketoglutarate -> Succinyl-CoA
+NADH
+CO2
+H

123
Q

Succinyl-CoA Synthetase

[GDP + Pi]

A

Succinyl-CoA -> Succinate
+GTP
+CoA

124
Q

a-Ketoglutarate Dehydrogenase Regulation

A

Activated by Ca, AMP

Inhibited by NADH, Succinyl-CoA

125
Q

Net Outcome of Respiration

A

2 ATP [Glycolysis]
2 NADH [Glycolysis] = 4 ATP
8 NADH [PyDh+CAC] = 24 ATP
2 FADH2 [CAC] = 4 ATP

Total = ~35

126
Q

Characteristics of Lipids

A

Insoluble in water, soluble in nonpolar organic solves

i.e. Hydrophobic, Lipophilic

127
Q

Citric Acid Cycle Products [In Order]

A

Acetyl-CoA + Oxaloacetate -> Citrate -> Isocitrate -> Alpha-Ketoglutarate -> Succinyl-CoA -> Succinate -> Fumarate -> Malate

128
Q

When is GTP Produced in the CAC?

A

From the Succinyl-CoA Dehydrogenase reaction

129
Q

CAC Mnemonic

A

Citrate Alone Is Often Kreb’s Starting Substrate For Making Oxaloacetate

130
Q

Regulation of Pyruvate Dehydrogenase

A

Inhibited by high levels of Acetyl-CoA, NADH

131
Q

Sphingophospholipids

A

Sphingolipids with a phosphodiester bond

132
Q

Sphingomyelins

A

Contain phosphatidylcholine or phosphatidylethanolamine; component of the myelin sheath

133
Q

Glycosphingolipids, Cerebrosides, Globosides

A

Sugar moieties attached instead of a phosphate group
Cerebrosides = monosaccharide connected to sphingosine
Globosides = disaccharide
Gangliosides = oligosaccharide (w/ N-acetylneuraminic acid)

134
Q

Waxes

A

Long chain fatty acids esterified to long chain alcohols; used for protection against evaporation and parasites in plants and animals

135
Q

a-Ketoglutarate Dehydrogenase Regulation

A

Activated by Ca, AMP

Inhibited by NADH, Succinyl-CoA

136
Q

Net Outcome of Respiration

A

2 ATP [Glycolysis]
2 NADH [Glycolysis] = 4 ATP
8 NADH [PyDh+CAC] = 24 ATP
2 FADH2 [CAC] = 4 ATP

Total = ~35

137
Q

Characteristics of Lipids

A

Insoluble in water, soluble in nonpolar organic solves

i.e. Hydrophobic, Lipophilic

138
Q

Phospholipids

A

Amphipathic (hydrophilic head, hydrophobic tail)

139
Q

Phosphodiester Linkage

A

Links the polar head to the tail; determines the function of the phospholipid

140
Q

Sesquiterpenes

A

3 Isoprene Units

141
Q

Sphingolipids

A

Contain a sphingosine backbone

142
Q

Steroid Hormones

A

Have high affinity receptors, work at low concentrations, affect gene expression & metabolism; derived from cholesterol

Glucocorticoids [Cortisol], Mineralocorticoids [Aldosterone], Estrogen, Progesterone, Testerone

143
Q

Sphingomyelins

A

Contain phosphatidylcholine or phosphatidylethanolamine; component of the myelin sheath

144
Q

Prostaglandins

A

Autocrine & Paracrine Hormones that regulate cAMP levels; affect muscle contraction, body temperature, sleep-wake cycle and pain

145
Q

Waxes

A

Long chain fatty acids esterified to long chain alcohols; used for protection against evaporation and parasites in plants and animals

146
Q

Vitamin D [Cholecalciferol]

A

Metabolized to calcitriol; regulates calcium and phosphorus homeostasis; promotes bone formation; deficiency = rickets

147
Q

Vitamin E [Tocopherols]

A

Biological antioxidants, destroy free radicals and prevent oxidative damage

148
Q

Vitamin K [Phylloquinone & Menaquinone]

A

Formation of prothrombin (clotting factor)

149
Q

Diterpene

A

4 Isoprene Units

150
Q

Triterpene

A

6 Isoprene Units

151
Q

Adipocytes

A

Animal cells that are used for storage of large triacylglycerol deposits

152
Q

Saponification

A

The ester hydrolysis of triacylglycerols using a strong base

153
Q

Lipase (Digestion)

A

Breaks down Triacylglycerols to fatty acids and monoglycerides through hydrolysis

154
Q

Emulsifcation

A

Breaks down fat globules into emulsion droplets; increases the surface area for digestion

155
Q

Colipase

A

A protein that binds to lipase at the surface of the emulsion droplets

156
Q

Oxidation of Fatty Acids

A

Occurs in the Matrix of the Mitochondria; Ester Hydrolysis in the Cytosol

157
Q

Vitamin E [Tocopherols]

A

Biological antioxidants, destroy free radicals and prevent oxidative damage

158
Q

Vitamin K [Phylloquinone & Menaquinone]

A

Formation of prothrombin (clotting factor)

159
Q

Why are triacylglycerols the preferred form of energy storage?

A

They are reduced and anhydrous which allow them to have a greater caloric yield; allows survival for about several weeks

They are not hydrated by the body and do not carry additional weight

160
Q

Triacylglycerols

A

One glycerol attached to 3 fatty acids by ester bonds

161
Q

Lipid Mobilization

A

Adipocytes -> Hormone-Sensitive Lipase

Lipoproteins -> Lipoprotein Lipase

162
Q

Saponification

A

The ester hydrolysis of triacylglycerols using a strong base

163
Q

Lipase

A

Breaks down Triacylglycerols to fatty acids and monoglycerides through hydrolysis

164
Q

Emulsifcation

A

Breaks down fat globules into emulsion droplets; increases the surface area for digestion

165
Q

Colipase

A

A protein that binds to lipase at the surface of the emulsion droplets

166
Q

Chylomicrons

A

Packaged groups of lipoprotein particles that are transported into enterocytes

167
Q

Apoproteins

A

Control interactions between lipoproteins

168
Q

Cholesterol Metabolism

A

Obtained through dietary sources or de novo synthesis in the liver

169
Q

Enzyme of Cholesterol Biosynthesis

A

HMG-CoA Reductase

170
Q

Short Chain Fatty Acids

A

Absorbed across the intestine into the blood

171
Q

CETP Enzyme

A

Catalyzes transition of IDL to LDL by transferring cholesteryl esters from HDL

172
Q

Lipid Mobilization

A

Adipocytes -> Hormone-Sensitive Lipase

Lipoproteins -> Lipoprotein Lipase

173
Q

Where are fatty acids synthesized?

A

In the cytoplasm from Acetyl-CoA transported out of the mitochondria

174
Q

Chylomicrons

A

Transport mechanism for dietary TAG molecules and are transported via lymphatic system

175
Q

Where are fatty acids oxidized?

A

In the mitochondria following transport by carnitine shuttle

176
Q

Acetyl-CoA Shuttling

A

Citrate is shuttled across the mitochondrial membrane into the cytosol and is split by citrate lyase; Oxaloacetate is then returned to to the mitochondria to continue shuttling Acetyl-CoA

177
Q

HDL

A

Reverse transport of cholesterol

178
Q

Fatty Acid Synthase

A

Adds group to ACP and continuously extends the chain using NADPH

179
Q

Cholesterol Metabolism

A

Obtained through dietary sources or de novo synthesis in the liver

180
Q

Enzyme of Cholesterol Biosynthesis

A

HMG-CoA Reductase

181
Q

LCAT Enzyme

A

Catalyzes formation of cholesteryl esters for transport with HDL

182
Q

CETP Enzyme

A

Catalyzes transition of IDL to LDL by transferring cholesteryl esters from HDL

183
Q

Process of Fatty Acid Synthesis

A

Activation -> Bond Formation -> Reduction -> Dehydration -> Reduction
-Repeated 8 times to form palmitic acid-

184
Q

Carnitine Acyltransferase II

A

Converts Acylcarnitine back to Acyl-CoA

185
Q

Beta-Oxidation Enzymes (Even)

A
  1. Fatty Acyl-CoA Dehydrogenase
  2. Enoyl-CoA Hydratase
  3. Thiolase
186
Q

Where are fatty acids oxidized?

A

In the mitochondria following transport by carnitine shuttle

187
Q

Beta-Oxidation Enzymes (Monounsaturated)

A
  1. Enoyl-CoA Isomerase
  2. Fatty Acyl-CoA Dehydrogenase
  3. Enoyl-CoA Hydratase
  4. Thiolase
188
Q

Beta-Oxidation Enzymes (Polyunsaturated)

A
  1. Dienoyl-CoA Reductase

2. Enoyl-CoA Isomerase

189
Q

Ketone Bodies

A

Acetoacetate, B-Hydroxybutyrate

190
Q

Ketogenesis

A

Occurs in the MTC of Liver Cells when excess Acetyl-CoA accumulates; ketone bodies are used for energy

191
Q

Fatty Acid Entry

A

Involves Carnitine Acyltransferase I; 2-12 Carbons diffuse into MTC, 14-20 carbons utilize Carnitine Shuttle

192
Q

Carnitine Shuttle Enzymes

A

Carnitine Palmitoyltransferase I
Carnitine Acylcarnitine Translocase
Carnitine Acyltransferase II

193
Q

HMG-CoA Lyase

A

HMG-CoA -> Acetoacetate -> B-Hydroxybutyrate

194
Q

Ketolysis

A

Regenerates Acetyl-CoA for use as an energy source in peripheral tissues

195
Q

Carnitine Acyltransferase II

A

Converts Acylcarnitine back to Acyl-CoA

196
Q

Ketolysis in the Brain

A

Brain begins to use ketone bodies and derive up to two-thirds of its energy during prolonged starvation; Ketones are metabolized to Acetyl-CoA, Pyruvate Dehydrogenase is inhibited in the brain

197
Q

Beta-Oxidation Enzymes (Odd)

A
  1. Propionyl-CoA Carboxylase

2. Methylmalonyl-CoA Mutase

198
Q

Beta-Oxidation Enzymes (Monounsaturated)

A

Enoyl-CoA Isomerase

199
Q

Beta-Oxidation Enzymes (Polyunsaturated)

A

Dienoyl-CoA Reductase

200
Q

Non-Template Synthesis of Lipids

A

DHAP - > Phosphatidic Acid -> Diglyceride [+Acyl CoA] -> Triglyceride

201
Q

Non-Template Synthesis of Polysaccharides

A

Hexokinase -> Phosphoglucomutase -> G1P UDP Transferase -> Glycogen Synthase

202
Q

Ketogenesis Enzymes

A

HMG-CoA Synthase

HMG-CoA Lyase

203
Q

Pyruvate Dehydrogenase Phosphotase

A

Activates PDH when ADP levels are high

204
Q

Electron Transport Chain

A

Takes place on the matrix-facing surface of the inner mitochondrial membrane; creates a proton gradient that pumps protons into the ATP synthase in order to produce ATP

205
Q

Complex I
[NADH-CoQ Oxidoreductase]
(4 Protons)

A

Transfers electrons from NADH -> FMN -> CoQ forming CoQH2

206
Q

Complex II
[Succinate-CoQ Oxidoreductase]
(No Protons)

A

Transfers electrons from Succinate -> FAD -> CoQ forming CoQH2

207
Q

Ketolysis in the Brain

A

Brain begins to use ketone bodies and derive up to two-thirds of its energy during prolonged starvation; Ketones are metabolized to Acetyl-CoA, Pyruvate Dehydrogenase is inhibited

208
Q

Complex IV
[Cytochrome c oxidase]
(2 Protons)

A

Transfers electrons in the form of hydride ions from Cyt c to Oxygen forming Water

209
Q

Transamination/Deamination

A

Loss of an amino acids amino group that allows the carbon skeleton to be used for energy

210
Q

Malate-Aspartate Shuttle

A

Electrons transferred from NADH to Oxaloacetate, forming malate which crosses the inner mitochondrial membrane and transfers electrons to NAD+

211
Q

Non-Template Synthesis of Lipids

A

DHAP - > Phosphatidic Acid -> Diglyceride [+Acyl CoA] -> Triglyceride

212
Q

Flavoproteins

A

Function as specific electron acceptors for dehydrogenases

213
Q

Cytochromes

A

Water soluble electron carries that contain iron pigments

214
Q

Pyruvate Dehydrogenase Phosphotase

A

Activates PDH when ADP levels are high

215
Q

Electron Transport Chain

A

Takes place on the matrix-facing surface of the inner mitochondrial membrane; creates a proton gradient that pumps protons into the ATP synthase in order to produce ATP

216
Q

Chemiosmotic Coupling

A

Electron transfer is coupled to ATP synthesis via the proton electrochemical gradient

217
Q

Complex II
[Succinate-CoQ Oxidoreductase]
(No Protons)

A

Transfers electrons from Succinate -> FAD -> CoQ forming CoQH2

218
Q

Complex III
[CoQH2-cytochrome c Oxidoreductase]
(4 Protons)

A

Transfers electrons from CoQH2 -> Heme forming Cyt c

219
Q

Complex IV
[Cytochrome c oxidase]
(2 Protons)

A

Transfers electrons in the form of hydride ions from Cyt c to Oxygen forming Water

220
Q

F1 Portion of ATP Synthase

A

Uses energy released by the gradient to phosphorylate ADP into ATP

221
Q

Malate-Aspartate Shuttle

A

Electrons transferred from NADH to Oxaloacetate, forming malate which crosses the inner mitochondrial membrane and transfers electrons to NAD+

222
Q

NADPH

A

Reducing Agent that drives anabolic reactions

223
Q

Flavoproteins

A

Function as specific electron acceptors for dehydrogenases

224
Q

Cytochromes

A

Water soluble electron carries that contain iron pigments

225
Q

Proton-Motive Force

A

Electrochemical gradient generated by the ETC across the inner mitochondrial membrane

226
Q

MTC Intermembrane Space

A

Higher concentration of protons than the matrix; stores energy

227
Q

Hormones that Regulate Metabolism

A

Insulin, Glucagon, Glucocorticoids (Cortisol), Catecholamines (Epinephrine and Norepinephrine), Thyroid Hormones

228
Q

Uncoupling Reagents

A

Block oxidative phosphorylation by dissipating the electrochemical gradient

229
Q

Glucagon Effects on Metabolism

A
  • Increases rate of catabolic metabolism
  • Increases blood glucose by stimulating gluconeogenesis, glycogenolysis
  • Secreted by alpha cells of pancreas
230
Q

Glucocorticoids Effects on Metabolism

A

Increase blood glucose in response to stress by mobilizing fat stores and inhibiting glucose uptake
-Increases the impact of glucagon and catecholamines

231
Q

Catecholamines Effects on Metabolism

[Epinephrine and Norepinephrine]

A

Promotes glycogenolysis and increases basal metabolic rate through their sympathetic nervous system activity

232
Q

Energetic Yield

  • Glycolysis
  • PDH
  • CAC
A

Glycolysis [2 NADH + 2 ATP]
PDH [2 NADH]
CAC [6 NADH, 2 FADH2, 2 GTP]

233
Q

NADH ATP Yield

A

2.5 ATP per NADH

234
Q

FADH2 ATP Yield

A

1.5 ATP per NADH

235
Q

Optimal ATP yield per Glucose

A

30-32 ATP

236
Q

Postprandial State

A

Well fed, insulin secretion is high and anabolic metabolism is high

237
Q

Postabsorptive State

A

Fasting, insulin secretion decreases while glucagon and catecholamine secretion increases; transition to catabolic metabolism

238
Q

Hormones that Regulate Metabolism

A

Insulin, Glucagon, Glucocorticoids (Cortisol), Catecholamines, Thyroid Hormones

239
Q

Brain & Nervous Tissue Metabolism

A

Consumes glucose mostly but in prolonged fasting, ketone bodies are used.

240
Q

Glucagon Effects on Metabolism

A
  • Increases rate of catabolic metabolism
  • Increases blood glucose by stimulating gluconeogenesis, glycogenolysis
  • Secreted by alpha cells of pancreas
241
Q

Glucocorticoids Effects on Metabolism

A

Increase blood glucose in response to stress by mobilizing fat stores and inhibiting glucose uptake
-Increases the impact of glucagon and catecholamines

242
Q

Catecholamines Effects on Metabolism

[Epinephrine and Norepinephrine]

A

Promotes glycogenolysis and increases basal metabolic rate through their sympathetic nervous system activity

243
Q

Thyroid Hormones

[T3 & T4]

A

Modulates the impact of other metabolic hormones and have a direct impact on basal metabolic rate
-T3 is more potent than T4

244
Q

Liver Metabolism

A

Responsible for maintenance of blood glucose levels by glycogenolysis and gluconeogenesis in response to pancreatic hormone activity; also processes lipids and cholesterol, bile, urea and toxins

245
Q

Adipose Tissue Metabolism

A

Stores lipids under the influence of insulin and releases them under the influence of epinephrine

246
Q

Skeletal Muscle Metabolism [Resting]

A

Conserves carbohydrates in glycogen stores and uses free fatty acids in the blood stream

247
Q

Skeletal Muscle Metabolism [Active]

A

Anaerobic Metabolism, OXPHOS, Direct phosphorylation from creatine phosphate or beta oxidation

248
Q

Cori Cycle

A

Lactate -> Gluconeogenesis -> Glucose

Between Liver & Muscle

249
Q

Cardiac Muscle Metabolism

A

Uses fatty acid oxidation, uses creatine phosphate

250
Q

Brain & Nervous Tissue Metabolism

A

Consumes glucose mostly but in prolonged fasting, ketone bodies are used.

251
Q

Hormones that regulate body mass

A

Leptin, Ghrelin & Orexin