Chapter 8: Metabolism Flashcards
Metabolism
Metabolism
Sum of all chemical reactions in a body (or cell, unit, etc.)
Anabolism
2+ molecules combine to form larger ones
Catabolism
Split large molecule into 2+ smaller ones
What type of energy is synonymous with potential energy?
Chemical energy
1st Law of Thermodynamics
Energy is neither created nor destroyed
2nd Law of Thermodynamics
In a closed system, entropy is always increasing
What do the variables in the Free Energy equation represent? ΔG=ΔH-TΔS
ΔG: Free energy released (negative/exergonic) or absorbed (positive/endergonic)
ΔH: Enthalpy (potential energy, total heat in a system)
T: temperature (in Kelvin)
ΔS: Entropy (disorder, if organized/complex=LOW)
Why do we need both endergonic and exergonic reactions?
Coupling them together allows the free energy of an exergonic reaction to fuel an endergonic one and vice versa
How is ATP used to make energy?
ATP + H2O (hydrolysis) –> P + ADP + energy
Enzymes
They lower activation energy needed to start a reaction
Cofactors
metal ions which help enzymes function as catalysts (efficient, not consumed)
Competitive inhibition
Molecule competes with substrate for access to active site
Noncompetitive inhibition
Inhibitor bonds to allosteric site, preventing the bonding of a substrate. However, they can be bound at the same time.
Allosteric regulation
Molecule binds to enzyme away from and separated from active site, limiting reactivity
Oxidation
Molecule is broken up, loses electrons (LEO)
