FINAL Flashcards
Phosphagen System, Phosphocreatine (PCr) System, and Creatine Phosphate System are typically known as what pathway?
ATP-PC system
What is the cellular location of the ATP-PC pathway?
Mitochondria and cytosol
What is the key enzyme of the ATP-PC pathway?
Creatine kinase
What is the co-factor of the ATP-PC pathway?
Mg
What are the reactants/stimulators of the ATP-PC pathway? (2)
ADP (low energy) and PCr
What are the products/inhibitors of the ATP-PC pathway? (2)
ATP (high energy) and Cr
What pathway/system produces ATP the fastest?
ATP-PC system
Excess reactants have what affect a pathway/enzyme?
stimulates
Scarce reactants have what affect on a pathway/enzyme?
inhibits
Excess products have what affect on a pathway/enzyme?
inhibits
Scarce products have what affect on a pathway/enzyme?
stimulates
What is secreted in response to high blood glucose?
- Lowers blood glucose to baseline values
- Increases glucose in fat and muscle cells
(Ex: Fat synthesis, glycogen synthesis, glycolysis)
insulin
What is secreted in response to low blood glucose?
- Increases blood glucose levels
- Causes the LIVER to release glucose from storage (glycogen)
- Causes the LIVER to make glucose (gluconeogenesis)
glucagon
What pathway breaks down carbohydrates anaerobically?
Glycolysis
Glycolysis is a precursor to what two pathways?
Krebs Cycle and ETS (electron transport system)
Where in the cell does glycolysis occur?
Cytosol
What are the key enzymes in glycolysis? (4)
- Hexokinase/Glucokinase
- Phosphofructokinase (PFK)
- Pyruvate kinase
- Lactate dehydrogenase
What is the rate limiting step in glycolysis?
PFK
What enzyme in glycolysis is stimulated by insulin and fructose, but inhibited by glucose-6-phosphate?
glucokinase
What are the reactants/stimulators of glycolysis? (6)
- Glucose
- ADP
- AMP
- NAD+
- Pi
- Insulin secretion
What are the products/inhibitors of glycolysis? (5)
-ATP
-NADH
-Pyruvate
o Fast – pyruvate to lactic acid and alanine
o Slow – pyruvate to mitochondria to aerobic metabolism
-Lactic acid
-Alanine
Citric acid cycle and Tricarboxylic acid cycle are synonymous name for which pathway?
Krebs cycle
Where does the Krebs cycle happen?
Mitochondrial matrix
What are the key enzymes in the Krebs cycle? (4)
- Isocitrate dehydrogenase
- alpha-ketoglutarate dehydrogenase
- succinate dehydrogenase
- malate dehydrogenase
(“IASM”)
What are the reactants/stimulants of Krebs cycle? (6)
- fat
- carbs
- protein oxidation
- acetyl CoA
- NAD+
- FAD
What are the products/inhibitors of Krebs cycle? (6)
- NADH
- FADH2
- GTP
- CO2
- ATP
- citrate
What is the location of ETS?
inner mitochondrial membrane
What is the key enzyme of the ETS?
dehydrogenases
What are the reactants/stimulants of the ETS? (5)
- ADP
- Pi
- NADH
- FADH2
- oxygen
What are products/inhibitors of the ETS? (3)
- ATP
- CO2
- H2O
FA oxidation is also known as what?
Beta oxidation
What are the four steps of B-oxidation?
(OHOT) oxydation, hydration, oxydation, thiolysis
What are the 2 essential fatty acids that cannot be synthesized in the body and must be acquired in the diet?
linoleic and alpha-linolenic
What is the location of B-oxidation?
mitochondrial matrix
Where in the cell is FA activated?
outer mitochondrial matrix
What is the key enzyme and rate limiting step in B-oxidation?
CPT 1 (carnitine complex)
What are the reactants/stimulants of FA oxidation? (9)
- exercise
- fasting
- high AMP (cAMP)
- AMPk
- Norepinephrine
- epinephrine
- ACTH
- low energy
- low blood glucose
What are the products/inhibitors of FA oxidation? (5)
- acetyl CoA
- insulin
- high glucose
- high malonyl CoA
- high energy
What are the only ketogenic amino acids?
leucine and lysine
Where in the cell does ketogenesis occur?
Mitochondrial matrix (Liver)
What are the key enzymes of ketogenesis? (2)
- HMG CoA Synthase (Rate limiting)
- Pyruvate carboxylase
What is the rate limiting step of ketogenesis?
HMG CoA Synthase
What is the Cofactor for ketogenesis?
Biotin
What are the reactants/stimulants of ketogenesis? (6)
- Acetyl CoA
- Low energy
- Low/no cholesterol
- Low blood sugar
- Epinephrine
- Glucagon
What are the products/inhibitors of ketogenesis? (4)
- Ketone bodies
- High energy
- High blood sugar
- Insulin
Glycogenolysis is also known as what?
glycogen degradation
Where in the cell does glycogen degradation occur?
Cytosol
What are the key enzymes of glycogen degradation? (5)
- Glycogen phosphorylase (Rate limiting)
- phosphoglucomutase
- Glucosyl-(4:4)-transferase
- Amylo-alpha-(1,6)-glucosidase
- Phosphorylase kinase (substrate – calmodulin)
What is the Cofactor of glycogen degradation?
Pyridoxal phosphate
What are the reactants/stimulants of glycogen degradation? (8)
- Low ATP
- Low levels of glucose
- Glucagon (liver)
- Epinephrine
- Norepinephrine
- Exercise/muscle contraction (Calcium)
- Low blood sugar
- Fasting (liver)
What are the products/inhibitors of glycogen degradation? (6)
- Glucose-1-phosphate
- Lots of ATP
- High levels of glucose
- Insulin
- High blood sugar
What amino acids are oxidizes in the muscles in relation to amino acid metabolism?
LIV GAA
leucine, isoleucine, valine, glutamate, aspartate, asparagine
Where in the cell does amino acid metabolism occur?
Cytosol (except Carbamoyl phosphate which is in mitochondrial matrix)
What are the key enzymes of amino acid metabolism? (2)
- Alanine Aminotransferase (ALT)
- Glutamine synthetase
What is the Cofactor for amino acid metabolism?
Pyridoxal phosphate
What are the reactants/stimulants of amino acid metabolism? (6)
- Low energy
- Low glucose
- Exercise
- Fasting
- Too much protein
- Protein turnover
What are the products/inhibitors of amino acid metabolism? (3)
- High energy
- High glucose
- Insulin
Where in the cell does fat synthesis occur?
Cytosol
What is the key enzyme and rate limiting step of fat synthesis?
Acetyl CoA Carboxylase (Rate limiting)
What is the Cofactor for fat synthesis?
Biotin
What are the reactants/stimulants of fat synthesis? (10)
- High Energy/ATP
- Insulin
- Glucose
- Acetyl CoA
- Galactose
- Fructose
- NADH
- FADH2
- Citrate
- Sugar
What are the products/inhibitors of fat synthesis? (3)
- Low energy
- ADP/AMP
- Glucagon
Where in the cell does cholesterol synthesis occur?
Cytosol
What is the key enzyme and rate limiting step for cholesterol synthesis?
HMG CoA Reductase (Rate limiting)
What are the reactants/stimulants of cholesterol synthesis?
-ATP
-NADPH
-Acetyl CoA
-O2
Insulin & Thyroxine
-Glucose & Fructose
-Low sterol levels
What are the products/inhibitors of cholesterol synthesis?
- ADP/AMP
- NADP+
- Glucagon
- Glucocorticoids
- Statins
- High sterols
- AMP Kinase
What is the location of gluconeogenesis?
mitochondria and the cytosol
What are the key enzymes of gluconeogenesis? (5)
- Glucose-6-Phosphate
- Fructose-1,6-BP
- PEP Carboxykinase
- Pyruvate Carboxylase
- Glycerol (3) phosphate dehydrogenase
What are the 2 cofactors of gluconeogenesis?
- biotin
- Mg2+
What are the reactants/stimulants of gluconeogenesis? (5)
- Glucagon
- Acetyl CoA
- Citrate
- ATP
- NADH
What are the products/inhibitors of gluconeogenesis?
- Glucose
- Insulin
- AMP/ADP
- Fructose-2,6-BP
What is the location of glycogen synthesis?
cytosol
What are the key enzymes of glycogen synthesis? (6)
- Glycogen Synthase (Rate limiting)
- Phosphoglucomutase
- UDP-glucose pyrophosphorylase
- Glycogen initiator synthase
- Glycogen synthase
- Glucosyl-4:6-transferase
What are the reactants/stimulants of glycogen synthesis? (5)
- ATP/high energy
- Lots of glucose
- Insulin
- Low glucagon
- Fructose
What are the products/inhibitors of glycogen synthesis? (5)
- AMP/ADP
- Low glucose
- Glucagon
- Muscle contraction
- Epinephrine
What are the two synonymous names of the Pentose Phophate pathway?
- Hexose monophosphate pathway
- Hexose monophosphate shunt
Oxidative reactions are ______ and non-oxidative reactions are _______.
irreversible; reversible
There is no ATP produced or consumed in the Pentose Phosphate pathway. T/F?
True
What are the key enzymes of the Pentose Phosphate pathway? (7)
- Glucose-6-Phosphate Dehydrogenase
- Cytochrome P450 mono-oxygenase system
- Superoxide dismutase
- Myeloperoxidase
- Catalase
- Glutathione peroxidase
- Glutathione reductase
What are the reactants/stimulants of the PPP? (2)
- Glucose-6-phosphate
- NADP+
What are the products/inhibitors of the PPP? (3)
- 6-Phosphoglucose S lactone
- NADPH
- Ribose-5-P
What is the location of Nucleotides - Purine Synthesis?
cytosol
What are the key enzymes of Nucleotides - Purine Synthesis? (2)
- Xanthine oxidase
- Ribonucleotide reductase
What are the reactants/stimulants of Nucleotides - Purine Synthesis?
?
What is the location of Nucleotides - Pyramidine Synthesis?
cytosol
What are the key enzymes of Nucleotides - Pyramidine Synthesis? (2)
- CAD
- Ribonucleotide reductase
What are the reactants/stimulants of Nucleotides - Pyramidine Synthesis?
?
What is the location of Alcohol metabolism?
cytoplasm of the liver
What is the location of MEOS (aka cytochrome P-450)?
endoplasmic reticulum
What are the key enzymes of Alcohol metabolism? (6)
- Alcohol dehydrogenase
- MEOS (aka: Cytochrome P-450)
- Catalase
- Acetaldehyde dehydrogenase
- Glycerol-3-phosphate dehydrogenase
- Krebs dehydrogenase
What is the reactant/stimulant of Alcohol metabolism?
NAD+
What are the products/inhibitors of Alcohol metabolism? (3)
- NADH
- Acetyl CoA
- Acetaldehyde