FOM 3.2.2 Flashcards
(11 cards)
Futile Cycle
when two metabolic pathways run simultaneously in opposite directions and have no overall effect other than to dissipate energy in the form of heat.
example: Glucose going back and forth from Glucose to G6P which helps with rapid response for up/downregulation
Near Equilibrium Reaction
- reaction goes back and forth
- example Creatine Kinase in muscles facilitate ATP being made by Phosphocreatine then being used by muscle (preworkout drink)
Essentially Irreversible
- products are so favored it’s essentially going one direction.
- In metabolism, equilibrium never reached so it basically won’t work backwards.
- Ex: azide modification of heme– the protein will likely be degraded before the azide dissociates
State Function
- delta G
- Independent of path
Equilibrium constant
Keq: magic ratio of products and reactant at equilibrium, the ratio the reaction is working towards
-Changing chemical nature of substrate or product will change this ratio
standard free energy
ΔG˚ = −RT ln K; this is derived at equilibrium when ΔG = 0 because potential energy is 0 at equilibrium. On the graph, it the vertical line that the reaction is working towards.
Oxidizing Agent:
-Drives reduction by accepting electrons (NAD+—> NADH)
Reducing Agent
-Reducing agent loses electrons via oxidation (Glyceraldehyde 3-P—–>1,3-Bisphosphoglycerate)
How does our body avoid equilibrium (death)?
-adding substrate (food) and removing product (CO2)
What enzyme can convert AMP + ATP to 2 molecules of ADP?
Adenylate Kinase
Free energy is independent of_enzyme or substrate____ and dependent on __enzyme or substrate_____
enzyme; substrate