Chapter 15 - Metabolism Flashcards
Energy is requires to meet which 3 fundamental needs?
muscle contraction, cell movement, and biosynthesis
Metabolic pathways can be…
linear, branched or circular
metabolites
intermediates in a metabolic pathways
reactants and products are referred as..
substrates and products
Usually, the first reaction of a metabolic pathways is…
irreversible, regulated and catalyzes a committed step
In order to construct a metabolic pathway, what two criteria must be met?
- the individual reaction must be specific
- the pathway in total must be thermodynamically favourable
A thermodynamically unfavourable reaction can be driven by..
coupling to a more favourable reaction
The _____ step regulates.
first
Metabolic pathways can be what two types?
- catabolic combusting carbon fuels to synthesize ATP
- anabolic using ATP and reducing power to synthesize large biomolecules
amphibolic pathways
can function anabolic ally or catabolically
first law of thermodynamics
total amount of energy in universe remains constant
second law of thermodynamics
entropy always increases
free energy
kind of energy that performs useful work at constant temperature and pressure
deltaG*=
-RTln(Keq) or -2.3RTlog(Keq)
ATP hydrolysis is…
exergonic
ATP has a high phosphorylation-transfer potential because of what 3 key factors?
- charge repulsion
- resonance stabilization
- stabilization by hydration
Which 3 molecules transfer high energy phosphate groups to ADP to create ATP?
- 1,3-BPG
- phosphoenolpyruvate (PEP)
- creatine phosphate
High energy molecules contain what kind of bonds?
anhydride-phosphate bonds
low energy molecules contain what kind of bonds?
ester bonds
reduction potential
measures affinity for electrons
Net potential is calculated as…
E’ for reduction reaction - E’ for oxidation reaction
When looking at standard reduction potentials, affinity and signage…..
is same whether it’s being oxidized or reduced
NAD+
nicotinamide adenine dinucleotide
FAD
Flavin Adenine Dinucleotide
Energetics of electron transfer equation
deltaG’=-nFE‘net
