MBS Biochemistry > Overview > Flashcards

Overview Flashcards

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1
Q

What is the definition of metabolism?

A

Metabolism is the sum of all changes in the body.

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2
Q

What is catabolism?

A

Catabolism takes larger molecules and breaks them down into smaller molecules.

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3
Q

What is anabolism?

A

Anabolism assembles larger/complex molecules from smaller ones.

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4
Q

What are the regulation levels of metabolism?

A
  1. Availability of substrates 2. Allosteric regulation 3. Covalent modification 4. Hormonal regulation
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5
Q

What is the absorptive state?

A

0-4 hours after eating; high glucose/high insulin; nutrients stored for later use.

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6
Q

What happens during the post-absorptive state?

A

4-24 hours after eating; low insulin/high glucagon; liver pumps out glucose; gluconeogenesis occurs.

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7
Q

What is the early starvation state?

A

1-5 days after eating; ketogenesis starts; glucagon stimulates fatty acid release from adipocytes.

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8
Q

What occurs in the late starvation state?

A

5+ days after eating; maximal skeletal muscle breakdown for alanine; gluconeogenesis shifts from 90% liver to 50:50 with kidney.

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9
Q

What are the sources of glucose?

A
  1. Diet 2. Glycogenolysis (liver) 3. Gluconeogenesis
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10
Q

What is glycogenolysis?

A

The process of breaking down glycogen into glucose, primarily occurring in the liver.

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11
Q

What is gluconeogenesis?

A

The synthesis of glucose from non-carbohydrate sources in the liver.

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12
Q

What is the role of glucagon in metabolism?

A

Glucagon promotes the mobilization of stored fuel and stimulates gluconeogenesis.

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13
Q

What happens to glucose in adipocytes?

A

In adipocytes, glucose can be converted to fats (triglycerol).

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14
Q

What is the function of ketogenesis?

A

Ketogenesis produces ketone bodies from fatty acids, primarily in the liver, during starvation.

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15
Q

What is the significance of alanine during late starvation?

A

Skeletal muscle pumps out alanine for gluconeogenesis in the liver.

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16
Q

What is the role of the kidney during late starvation?

A

The kidney pumps out glutamine to support gluconeogenesis.

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17
Q

What happens to skeletal muscle during late starvation?

A

Skeletal muscle undergoes maximal breakdown for alanine to support gluconeogenesis.

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18
Q

What is the effect of hormonal regulation on metabolism?

A

Hormonal regulation affects how the body uses hormones to store and mobilize energy.

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19
Q

What is the high insulin state associated with?

A

The absorptive state, characterized by high glucose and nutrient storage.

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20
Q

What is the low insulin state associated with?

A

The past-absorptive state, characterized by low insulin and high glucagon levels.

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21
Q

What is the main energy source for the brain and RBCs during the absorptive state?

A

Glucose is stored exclusively in the brain and red blood cells (RBCs).

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22
Q

What happens to glucose in the liver/skeletal muscle during the absorptive state?

A

Glucose is stored as glycogen in the liver and skeletal muscle.

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23
Q

What happens to glucose in the early starvation state?

A

Ketogenesis begins; glucagon stimulates fatty acids to be sent to the liver for beta oxidation.

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24
Q

What occurs during maximal skeletal muscle breakdown?

A

In late starvation, skeletal muscle breaks down to provide alanine for gluconeogenesis.

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25
What is the balance of gluconeogenesis in the late starvation state?
Gluconeogenesis is 50:50 between liver and skeletal muscle.
26
What is the role of insulin during the absorptive state?
Insulin promotes nutrient storage and lowers blood glucose levels.
27
What is the effect of glucagon on the liver?
Glucagon stimulates the liver to release glucose and perform gluconeogenesis.
28
What is the function of beta oxidation?
Beta oxidation breaks down fatty acids for energy production in the liver.
29
What are the key hormones involved in metabolic regulation?
Key hormones include insulin and glucagon.
30
What is the significance of ketone bodies during starvation?
Ketone bodies serve as an alternative energy source for the brain during starvation.
31
What happens in Type I Diabetes?
The immune system attacks/kills beta cells, preventing insulin production.
32
What is the source of insulin?
Beta cells in the Islet of Langerhans in the pancreas.
33
What type of receptor does insulin bind to?
Tyrosine kinase receptor.
34
What is the effect of insulin?
Promotes glucose storage as glycogen in the liver and muscle.
35
What regulates insulin secretion?
+++ Glucose, + Amino Acids, + Neural input.
36
What is the source of glucagon?
Alpha cells in the Islet of Langerhans in the pancreas.
37
What type of receptor does glucagon bind to?
G-Protein Coupled Receptor.
38
What is the effect of glucagon?
Prevents hypoglycemia and mobilizes nutrients.
39
What regulates glucagon secretion?
--- Glucose, --- Insulin, +++ Amino Acids, + Cortisol, + Epinephrine, + Norepinephrine.
40
What is the Km value for GLUT1?
Km: 1, found in RBCs, heart, blood-brain barrier, skeletal muscle.
41
What is the Km value for GLUT2?
Km: 15-20, found in liver, pancreas, kidney, hypothalamus, intestines.
42
What is the Km value for GLUT3?
Km: 1, found in brain (neurons) and leukocytes (WBCs).
43
What is the Km value for GLUT4?
Km: 5, found in adipocytes, heart, and skeletal muscle.
44
What is the Km value for GLUT5?
Km: 10, found in intestines.
45
How is fructose metabolized in the liver?
Fructose is converted to Fructose-6-Phosphate via Fructokinase, bypassing PFK1.
46
How is galactose metabolized in the liver?
Galactose is converted to Galactose-1-Phosphate via Galactokinase, then to UDPGalactose and UDPGlycogen
47
What can slow down glycolysis?
PEP IPH
48
What is the first step of glycolysis?
Irreversible Hexokinase converts Glucose to Glucose-6-P
49
What does PFK1 convert?
Converts Fructose-6-P to Fructose-1,6-BP Irreversible step
50
What are the products of glycolysis?
2 Pyruvate 2 ATP 2 NADH
51
What is the role of GAPDH in glycolysis?
Catalyzes the conversion of Glyceraldehyde-3-P Produces first high-energy phosphate bond
52
What inhibits GAPDH?
Low NAD levels
53
What are the symptoms of glycolysis dysfunction?
Jaundice Splenomegaly Fatigue
54
What is the last step of glycolysis?
Converts Phosphoenolpyruvate to Pyruvate Irreversible and regulated by F16BP
55
What is the effect of ATP on glycolysis?
Inhibits PFK1 Inhibits Pyruvate Kinase
56
What are the two isoforms of Pyruvate Kinase (PK)?
PKL (liver) PKR (RBCs)
57
What does PFK1 stand for?
Phosphofructokinase 1
58
What is the function of Phosphoglycerate Kinase?
Converts 1,3-Bisphosphoglycerate to 3-Phosphoglycerate
59
How many NAD+ are used in glycolysis?
2 NAD+
60
What is the role of Insulin in glycolysis?
Activates PKL by dephosphorylation
61
What is formed under anaerobic conditions?
Lactate
62
What is the final product of glycolysis?
2 Pyruvate
63
What is GLUT unable to recognize?
Glucose-6-P
64
What are the two forms of Pyruvate Kinase?
PKL (liver) PKR (RBCs)
65
What does AMP do in glycolysis?
Speeds up PFK1
66
What is the role of Aldolase in glycolysis?
Converts Fructose-1,6-BP to Triose Phosphate
67
What does Enolase convert?
Converts 2-Phosphoglycerate to Phosphoenolpyruvate
68
What is the first committed step in glycolysis?
Conversion of Fructose-6-P to Fructose-1,6-BP by PFK1
69
What is the significance of NADH in glycolysis?
Reduced form of NAD+ Used in energy production
70
What is the function of Phosphoglucose Isomerase?
Converts Glucose-6-P to Fructose-6-P
71
What is the significance of 2 ADP in glycolysis?
Used to produce 2 ATP
72
What is the role of Citrate in glycolysis?
Inhibits PFK1 and Pyruvate Kinase
73
What is F26BP?
Fructose-2,6-bisphosphate Activator of PFK1
74
What does ADPL stand for?
Adenosine diphosphate (ADP, used in ATP production)
75
What is the role of Phosphoglycerate Mutase?
Converts 3-Phosphoglycerate to 2-Phosphoglycerate
76
What is the function of Triose Phosphate Isomerase?
Converts DHAP to Glyceraldehyde-3-P
77
What is the role of 2 NADH in glycolysis?
Produced during the conversion of Glyceraldehyde-3-P
78
What is the significance of high insulin levels?
Activates PKL isoform
79
What does G6P stand for?
Glucose-6-phosphate
80
What does Pyruvate convert to under aerobic conditions?
Acetyl-CoA
81
What is the role of 2-Phosphoglycerate in glycolysis?
Intermediate in the pathway
82
What does ADP stand for?
Adenosine diphosphate
83
What are the key enzymes in glycolysis?
Hexokinase PFK1 Pyruvate Kinase
84
What is the effect of Alanine on glycolysis?
Inhibits Pyruvate Kinase
85
What is the energy yield of glycolysis?
2 ATP per glucose molecule
86
What is the function of lactate in glycolysis?
Produced under anaerobic conditions
87
What is the role of CO2 in glycolysis?
Byproduct of pyruvate conversion
88
What does Glyceraldehyde-3-P produce?
2 molecules during glycolysis
89
What is the significance of high ATP levels?
Inhibits glycolysis
90
What is the role of liver in glycolysis?
Regulates glucose levels through PKL
91
What is the function of DHAP in glycolysis?
Intermediary in the conversion to Glyceraldehyde-3-P
92
What does PFK2 do?
Regulates F26BP levels
93
What is the role of phosphate groups in glycolysis?
Energy transfer and storage
94
What is the function of Pyruvate Kinase?
Converts Phosphoenolpyruvate to Pyruvate
95
What is the role of insulin in liver glycolysis?
Activates PKL by dephosphorylation
96
What is the significance of 2 ATP in glycolysis?
Produced from ADP during glycolysis
97
What does Hexokinase do?
Converts Glucose to Glucose-6-P
98
What is the role of NAD+ in glycolysis?
Acts as an electron carrier
99
What is the overall reaction of glycolysis?
Glucose + 2 NAD+ + 2 ADP → 2 Pyruvate + 2 NADH + 2 ATP
100
What is the function of Phosphoenolpyruvate?
Precursor to Pyruvate
101
What does ATP stand for?
Adenosine triphosphate
102
What is the importance of glycolysis?
Primary pathway for glucose metabolism
103
What is the role of splenomegaly in glycolysis?
Indicates possible dysfunction in glycolysis
104
What is the function of 3-Phosphoglycerate?
Intermediate in glycolysis
105
What is the role of energy in glycolysis?
Essential for ATP production
106
What does 2-Phosphoglycerate convert to?
Phosphoenolpyruvate
107
What is the role of ATP in glycolysis?
Provides energy for reactions
108
What is the role of lactate in glycolysis?
End product under anaerobic conditions
109
What is the significance of citrate in glycolysis?
Inhibitor of PFK1
110
What is the role of ADP in glycolysis?
Used to generate ATP
111
What does F6P stand for?
Fructose-6-phosphate
112
What is the role of Glycolysis Diagram?
Illustrates the process and key steps
113
Where does ketogenesis occur?
Liver
114
What suppresses ketogenesis?
Insulin
115
What is the unit used to make ketone bodies?
Acetyl-CoA with fatty acids
116
What are the main ketone bodies produced?
Acetoacetate Beta-hydroxybutyrate Acetone
117
Which organs can use ketone bodies for energy?
Brain Heart Skeletal muscle
118
What pathway can G6P and F6P enter?
Pentose Phosphate Pathway
119
What are the products of the pentose phosphate pathway?
Ribose (for nucleotide synthesis) NADPH (for reductive reactions)
120
What deficiency impairs the ability to combat oxidative stress?
Glucose-6-Phosphate Dehydrogenase Deficiency
121
What condition does G6PD deficiency lead to?
Hemolytic anemia
122
What are Heinz bodies?
Damaged protein aggregations
123
What type of cells are created due to G6PD deficiency?
Bite cells
124
What is the function of the pentose phosphate pathway?
Important for cellular function
125
What is the main role of NADPH produced in the pentose phosphate pathway?
Used in reductive reactions
126
What is the function of the **mitochondria** in the cell?
Power grid of the cell, site of ATP synthesis, and TCA cycle ## Footnote Mitochondria are essential for energy production in eukaryotic cells.
127
What are the characteristics of the **outer membrane** of mitochondria?
Permeable to most small ions and molecules (porin) ## Footnote The outer membrane allows the passage of small molecules while maintaining the integrity of the mitochondria.
128
What is the **inner membrane** of the mitochondria like?
Folded into cristae ridges, impermeable to most molecules ## Footnote The folds increase surface area for ATP production.
129
What is the **matrix** of the mitochondria?
Site of the Citric Acid Cycle and Beta Oxidation ## Footnote The matrix contains enzymes necessary for metabolic processes.
130
What is **pyruvate** converted into?
Acetyl-CoA through oxidative decarboxylation ## Footnote This conversion is crucial for entering the TCA cycle.
131
What does the **PDH Complex** stand for?
Pyruvate Dehydrogenase Complex, made of E1, E2, E3 with cofactors ## Footnote The PDH Complex plays a key role in linking glycolysis to the TCA cycle.
132
What **vitamins** are associated with the PDH Complex?
* E₁ - Thiamin B₁ * E₂ - Lipoic Acid + CoA * E₃ - FAD + NAD (B₂ + B₃) ## Footnote These vitamins serve as cofactors necessary for the enzymatic reactions.
133
How is the PDH Complex **activated**?
Dephosphorylated by PDH Phosphatase; activated by Calcium release and muscle contraction ## Footnote Activation is crucial for energy metabolism during physical activity.
134
What causes **lactic acidosis** related to the PDH Complex?
Deficiency in Vitamin B₁ or alcoholism affecting E₁ ## Footnote Insufficient E₁ activity can lead to increased lactate levels.
135
What can **inhibit E₂** of the PDH Complex?
Inhibited by Arsenic and Mercury, leading to neurodegeneration ## Footnote These toxins disrupt normal cellular metabolism.
136
What does the **TCA Cycle** oxidize to produce?
* CO₂ * GTP * FADH₂ ## Footnote The TCA cycle is a central metabolic pathway in cellular respiration.
137
What is the total **ATP yield** per turn of the TCA Cycle?
10 ATP ## Footnote This yield includes contributions from NADH and FADH₂.
138
How much ATP is produced from **1 FADH₂** in the TCA Cycle?
1.5 ATP ## Footnote FADH₂ contributes to the electron transport chain.
139
How much ATP is produced from **3 NADH** in the TCA Cycle?
7.5 ATP ## Footnote NADH is a key electron carrier in oxidative phosphorylation.
140
What is the TCA Cycle classified as?
Amphibolic ## Footnote It serves both catabolic and anabolic functions.
141
What are the components of **oxidative phosphorylation**?
* Complexes I-IV * Mobile carriers: cytochrome C * Electron carriers: NADH/FADH₂ ## Footnote These components work together to produce ATP.
142
How does **NADH** shuttle electrons in oxidative phosphorylation?
NADH shuttles electrons to Complex I ## Footnote This initiates the electron transport chain.
143
How does **FADH₂** shuttle electrons in oxidative phosphorylation?
FADH₂ shuttles electrons to Complex II ## Footnote This is a different entry point into the electron transport chain.
144
What is the final **electron acceptor** in oxidative phosphorylation?
O₂ (oxygen) is the final electron acceptor ## Footnote Oxygen is essential for the production of ATP in aerobic respiration.
145
What do **Complexes 1, 3, and 4** do in oxidative phosphorylation?
They pump protons to create a proton gradient ## Footnote This gradient is used to drive ATP synthesis.
146
What is the role of **ATP Synthase** in oxidative phosphorylation?
ATP Synthase acts as a rotary motor driven by proton flow, converting ADP + Pi to ATP ## Footnote It is the final step in ATP production.
147
What is the **Glycerophosphate Shuttle**?
NADH uses GAPDH to convert DHAP to G3P. G3P transfers electrons to FADH₂ for Complex II. Yields 1.5 ATP ## Footnote This shuttle allows NADH to enter the mitochondria indirectly.
148
What is the **Malate Shuttle**?
NADH from GAPDH transfers electrons to oxaloacetate. Oxaloacetate is reduced to malate. Malate enters shuttle, yielding 2.5 ATP ## Footnote This shuttle is another mechanism for transporting reducing equivalents into the mitochondria.
149
What are some **inhibitors** of oxidative phosphorylation?
* Complex 1: Amobarbital * Complex 2: Malonate * Complex 3: Antimycin * Complex 4: Cyanide ## Footnote These inhibitors can disrupt ATP production and cellular respiration.
150
What do **uncoupler proteins (UCPs)** do in oxidative phosphorylation?
UCPs uncouple ATP synthesis from released energy, releasing energy as heat instead ## Footnote This process can lead to thermogenesis.
151
What is depicted in the **schematic diagram** of oxidative phosphorylation?
It shows Complexes I-IV, proton pumps, electron carriers, ATP synthase, and proton gradient generation ## Footnote This diagram illustrates the overall process of ATP production.
152
What is the main purpose of **gluconeogenesis**?
To make glucose (6 carbons) from 3-carbon precursors like lactate, alanine, and glycerol ## Footnote Gluconeogenesis is crucial for maintaining blood glucose levels during fasting.
153
Where does **gluconeogenesis** primarily occur?
* 90% in the liver * 10% in skeletal muscle * During starvation: 50% in liver and kidney ## Footnote The liver is the primary site for gluconeogenesis, especially during fasting.
154
Which enzyme converts **G6P** to glucose?
G-6-Pase, located in the ER's luminal surface ## Footnote This enzyme is essential for the final step of gluconeogenesis.
155
What does **F-1.6.BPase** do in gluconeogenesis?
Converts F16BP to F6P, bypassing the PFKI step of glycolysis ## Footnote This step is crucial for the regulation of gluconeogenesis.
156
What inhibits **F-1.6.BPase**?
* Inhibited by AMP * Inhibited by F26BP ## Footnote These inhibitors signal low energy states, reducing gluconeogenesis.
157
What is the function of **PEPCK** in gluconeogenesis?
Converts oxaloacetate to PEP, consuming 1 GTP and bypassing the pyruvate kinase step ## Footnote PEPCK is a key regulatory enzyme in gluconeogenesis.
158
What stimulates **pyruvate carboxylase**?
Stimulated by the build-up of Acetyl-CoA ## Footnote This activation is important for initiating gluconeogenesis.
159
What are the **precursors** for gluconeogenesis?
* Lactate * Alanine * Glycerol * TCA Cycle intermediates ## Footnote These precursors provide the necessary substrates for glucose synthesis.
160
How is **lactate** converted to pyruvate?
Oxidized by lactate dehydrogenase, producing NADH ## Footnote This conversion is part of the gluconeogenesis pathway.
161
What is the role of **glycerol** in gluconeogenesis?
Enters gluconeogenesis at the DHAP step after conversion to glycerol-3-phosphate ## Footnote Glycerol is derived from triglyceride breakdown.
162
What is produced from the breakdown of **triglycerides**?
Glycerol, which can enter gluconeogenesis ## Footnote This process provides an important energy source during fasting.
163
What can **TCA cycle intermediates** become in gluconeogenesis?
They can be converted to oxaloacetate ## Footnote This conversion links the TCA cycle to gluconeogenesis.
164
What is the **cofactor** used by pyruvate carboxylase?
Biotin, requires 1 ATP for the reaction ## Footnote Biotin is essential for the carboxylation reaction in gluconeogenesis.
165
What is the main source of **alanine** for gluconeogenesis?
Produced from skeletal muscle breakdown and converted to pyruvate by alanine amino transferase in the liver ## Footnote Alanine plays a significant role in gluconeogenesis during fasting.
166
What is the effect of increased **PEPCK** on gluconeogenesis?
Increases the rate of gluconeogenesis ## Footnote Higher levels of PEPCK enhance glucose production.
167
What is the primary shuttle for **Oxaloacetate** in gluconeogenesis?
Oxaloacetate must be converted to either Aspartate or Malate to travel across the mitochondrial membrane ## Footnote This conversion is necessary for the transport of intermediates.
168
How many **ATP** are required for gluconeogenesis?
4 ATP (equivalent to 6 ATP for 1 glucose molecule) ## Footnote The energy cost is significant for gluconeogenesis.
169
What provides energy for **gluconeogenesis**?
Energy is provided by beta oxidation under high glucagon and high lipolysis conditions ## Footnote This energy source is crucial during fasting states.
170
What are the **stimulators** of gluconeogenesis?
* High Glucagon → High cAMP * Cortisol → increased PEPCK ## Footnote These hormones promote gluconeogenesis during fasting.
171
What are the **inhibitors** of gluconeogenesis?
* Insulin ↓ PEPCK ↓ gluconeogenesis * High F26BP * High NADH/NAD+ ratio (alcohol metabolism) ## Footnote These factors signal the body to reduce glucose production.
172
What is the role of **Malate Dehydrogenase** in gluconeogenesis?
It reduces Oxaloacetate to Malate for transport out of the mitochondria ## Footnote This enzyme facilitates the movement of intermediates between compartments.
173
Where does **Pyruvate** enter for gluconeogenesis?
Pyruvate enters the mitochondria via the Pyruvate carrier ## Footnote This transport is essential for initiating gluconeogenesis.
174
What happens to **Oxaloacetate** in the cytosol?
It is converted to Aspartate via amination or reduced to Malate ## Footnote These conversions are necessary for gluconeogenesis.
175
What is the source of **energy** for gluconeogenesis?
Energy is derived from beta oxidation during high glucagon and lipolysis ## Footnote This energy source is critical during fasting.
176
What is the effect of high **NADH/NAD+ ratio** on gluconeogenesis?
It inhibits gluconeogenesis, especially in alcohol metabolism ## Footnote High NADH levels signal a reduced capacity for gluconeogenesis.
177
What is the structure of **glycogen**?
* Highly branched * Contains a1-4 bonds * Contains a1-6 bonds ## Footnote The structure of glycogen allows for rapid mobilization of glucose.
178
What stimulates **glycogenesis**?
High insulin levels ## Footnote Insulin promotes the storage of glucose as glycogen.
179
What is the role of **Glycogenin** in glycogenesis?
Synthesizes new glycogen by adding glucose (8) to itself ## Footnote Glycogenin acts as a primer for glycogen synthesis.
180
What is the pathway of glucose in **glycogenesis**?
Glucose → G6P → G1P → UDP-Glucose ## Footnote This pathway is essential for glycogen synthesis.
181
Which enzyme adds glucose via **a1-4 bonds** in glycogenesis?
Glycogen Synthase ## Footnote This enzyme is crucial for elongating glycogen chains.
182
What does the **Branching Enzyme** do in glycogenesis?
Creates a1,6 bonds once the chain gets longer ## Footnote This branching increases the solubility and mobilization of glycogen.
183
What drives **glycogenolysis**?
* Glucagon * Epinephrine ## Footnote These hormones trigger the breakdown of glycogen to glucose.
184
What is the first step in **glycogen breakdown**?
Conversion of glucose residues to Glucose-1-P by Glycogen Phosphorylase ## Footnote This step initiates glycogenolysis.
185
What converts **G1P** to G6P in glycogenolysis?
Phosphoglucomutase ## Footnote This enzyme facilitates the conversion necessary for glucose release.
186
How is **G6P** converted to Glucose?
By G6Pase ## Footnote This step is crucial for releasing glucose into the bloodstream.
187
What are the two activities of the **Debranching Enzyme**?
* a4:4 Transferase Activity * a1,6 Glucosidase Activity ## Footnote These activities are essential for complete glycogen breakdown.
188
How does **glycogenolysis** occur in skeletal muscle?
No glucagon receptor; activated by epinephrine, calcium influx, and increased AMP ## Footnote Muscle cells respond differently to hormonal signals compared to liver cells.
189
What is the role of **Protein kinase A** in glycogenolysis?
Activates Glycogen Phosphorylase via Phosphorylase Kinase ## Footnote This activation is crucial for glycogen breakdown.
190
What does the **Calcium-Ca2+-Calmodulin Complex** do in glycogenolysis?
Activates Glycogen Phosphorylase via Phosphorylase Kinase ## Footnote This complex plays a role in muscle contraction and glycogen mobilization.
191
What triggers **Glycogen Phosphorylase** in muscle contraction?
Increased AMP ## Footnote AMP acts as a signal for energy demand in muscle cells.
192
What is **Von Gierke Disease**?
Glycogen Storage Disease Type 1; deficiency in G6Pase; cannot mobilize Glucose ## Footnote Symptoms include enlarged liver/kidney, severe fasting hypoglycemia, lactic acidosis, lipidemia, and growth failure.
193
What is a key feature of **Pyruvate Carboxylate Deficiency**?
Rare disorder; cannot convert Pyruvate to Oxaloacetate; prohibits most gluconeogenesis ## Footnote Symptoms include failure to thrive, developmental delays, and seizures.
194
What causes **Alcohol-Induced Hypoglycemia**?
Ethanol metabolism leads to high NADH/NAD+ ratio; inhibits gluconeogenesis ## Footnote This occurs in the fasted state when glycogen stores are depleted.
195
What are the symptoms of **Von Gierke Disease**?
* Enlarged liver/Kidney * Severe fasting hypoglycemia * Lactic Acidosis * Lipidemia * Growth failure ## Footnote These symptoms are characteristic of this glycogen storage disease.
196
What is the treatment for **Von Gierke Disease**?
Dietary management ## Footnote This approach helps manage symptoms and prevent complications.
197
What are the symptoms of **Pyruvate Carboxylate Deficiency**?
* Failure to thrive * Developmental delays * Seizures ## Footnote These symptoms indicate significant metabolic dysfunction.
198
How does high **NADH/NAD+ ratio** affect gluconeogenesis?
It inhibits gluconeogenesis ## Footnote This effect is particularly relevant in the context of alcohol metabolism.
MBS Biochemistry
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