Unit 3 Flashcards
Thermodynamics (def)
How much NRG released as a reaction proceeds towards equilibrium
Negative ΔG (2)
Exergonic
Reaction proceed towards products
Positive ΔG (2)
Endergonic
Reaction proceed towards reactants
Enthalpy change (2)
Difference in bond energies between reactants and products
Formed - broken
Exothermic (3)
Release heat
Negative ΔH
More stable bonds formed
Endothermic (3)
Need heat input
Positive ΔH
Less stable bonds formed
Entropy (2)
Change in randomness
Increase in randomness is a positive ΔS
Standard conditions (def)
1M of each species
Product Favored (Keq & ΔG°)
Keq > 1
ΔG° < 1
Reactant Favored (Keq & ΔG°)
Keq < 1
ΔG° > 1
Glycolysis prep stage (2)
C6 → 2x C3
Put in 2 ATP
Glycolysis payoff stage (2)
2x C3 → 2x pyruvate + 4 ATP + 2 NADH
Net gain = 2 ATP + 2 NADH
Hexokinase Rxn (3)
Add phosphate from ATP to glucose (coupled)
Make glucose 6 phosphate
Highly favorable
Phosphohexose isomerase (2)
Glucose → fructose
Isomerize to break in half later
Phosphofructokinase (4)
Fructose 6 P + ATP→ fructose 1,6 bisphosphate + ADP
Add another phosphate to fructose
Put in 1 ATP
Favorable, coupled
Phosphofructokinase regulation
ATP regulates by binding to allosteric site (when high concentration)
Aldolase (1)
Hexose → 2 trioses
Triose phosphate isomerase (TPI)
Interconvert between trioses
Oxidation of glyceraldehyde 3 P (3)
Only redox reaction
Energy of oxidation preserved in phosphate bond + NADH
Dehydrogenase reaction
Phosphoglycerate kinase
(3)
First payoff
Coupled to substrate level phosphorylation
1, 3 Bisphosphoglycerate → 3 PGA
Phosphoglycerate mutase (3)
Rearrange molecule
Redistribute energy
3 Phosphoglycerate → 2 Phosphoglycerate
Formation of phosphoenolpyruvate
Create phosphoenolpyruvate
ATP from PEP (3)
Create pyruvate
Second payoff (1 ATP)
Favorable
Reactions in mitochondria
Citric acid cycle
Respiration
Reactions in cytoplasm
Glycolysis
Fermentation
Kinases
Add phosphate groups
Dehydrogenases
Oxidize the organic compounds and generate energy
Isomerases
Convert one isomer to another
Rearrange molecule
Aldolase
Break down sugars
Mutase
Type of isomerase
Move functional group on molecule
Pyruvate dehydrogenase complex
E1
Decarboxylation
Release CO2
Pyruvate dehydrogenase complex
E2
Oxidation
Byproduct is Acetyl CoA
Pyruvate dehydrogenase complex
E3
Shuttle electrons to NAD+
Create FADH2 intermediate
End product is NADH + H+
Regenerate lipoic acid
Where is NRG stored (pyruvate dehydrogenase reaction)
Thioester bond of acetyl CoA
NADH
Pyruvate converted to ethanol because
Ethanol is more oxidized than pyruvate
How to make reaction favorable with large Del G
Couple to ATP hydrolysis
Why is pyruvate converted to lactate
To replenish Nad+
Carnitine
Essential for transport of FA across mitochondrial membrane
Why is balanced photosynthesis equation not correct
O2 results from splitting H2O
6 H2O can’t form 6 O2
What occurs in the calvin cycle
NADPH and ATP are used to reduce CO bonds
Glycolysis Step 1
Favorable
Coupled to ATP breakdown
Glycolysis step 3
Favorable
ATP breakdown
Glycolysis step 4
Unfavorable
Le Chatelier’s principle
Glycolysis step 7
Favorable
Payoff
Glycolysis step 10
Favorable
Payoff
CAC Step 1
Favorable
Regulated
CAC step 3
Favorable
Payoff
CAC Step 4
Favorable
Payoff
CAC step 8
Positive del g
Conditions far from standard
FA Oxidation Steps
Activation
Transport
Oxidation
Beta Oxidation Steps
Dehydrogenation
Hydration
Dehydrogenation
Thiolytic cleavage
Cite of urea production
Liver
Outside NH4+ detoxified as
Glutamine
Alanine
Glucogenic
Converted to citric acid cycle intermediates
Ketogenic
Converted to acetate
Electron transport chain location
mitochondria
Glycolysis location
Cytoplasm
Light rxn
light + H2O –> NADPH + ATP + O2
Dark rxn
NADPH + ATP + CO2 –> Sugar
