Enzymes
enzyme
biological catalyst that speeds up chemical reactions
not used up
typically a protein
lowers energy requirements of a reaction
energy
the ability to do work
substrate
the molecule(s) an enzyme acts upon
ATP
adenosine tri-phosphate
cellular energy
potential energy
stored energy
kinetic energy
energy of motion
entropy
disorder
catabolic reactions
reactions that breakdown molecules into smaller ones
usually spontaneous
exergonic
exergonic
reaction that releases energy
endergonic
reactions that store energy
anabolic reactions
need an input of energy
not spontaneous
build larger molecules by joining smaller ones
Metabolism
sum of all the chemical reactions in an organism
Gibbs Free Energy
the amount of energy available to do work
delta G
negative delta G
reaction releases energy (exergonic)
spontaneous
products have less energy
positive delta G
net input of energy is needed
products have more energy
not spontaneous
Types of Cellular Work
Chemical Work
Transport Work
Mechanical Work
Energy Coupling
process where a spontaneous reaction (exergonic) fuels a non-spontaneous reaction (endergonic)
occurs in metabolic pathways
delta G will be negative
active site
location on an enzyme that the substrate binds to
induced fit
enzyme hug
when substrate binds at active site holds on tighter
activation energy
energy needed to make the reaction occur
denaturation
loss of proteins native structure
Factors that affect enzyme activity
temperature
pH
inhibitors
co-enzymes/co-factors
Feedback inhibition
when the product of a reactant binds the enzyme to prevent further reaction
competitive inhibitor
molecule that binds to the active site blocking substrate from binding
non-competitive inhibitor
molecule that binds to a location other than the active site and causes a conformational change
allosteric regulation
molecules that bind to a site on the enzyme and inhibits or activates its activity at another site.