Metabolism Flashcards
(20 cards)
Cell’s 3 types of work
Mechanical-movement
Transport-moving ions, particles
Chemical- reactions
All need ATP
Exergonic Reaction
Spontaneous
Net release of energy
Endergonic Reaction
Requires/ absorbs free energy
Non-spontaneous
ATP (Adenosine Triphosphate)
Cell’s energy shuttle
Energy comes from breaking phosphate bond- becomes ADP (Adenosine Diphosphate)
Provides energy for cellular functions
ATP Hydrolysis
Breaking bond
Can be coupled with other reactions
Anabolic Pathway
Build molecules from simpler ones
Consume energy
Catabolic Pathway
Break down complex molecules
Release energy
Hydrolysis
Chemical reaction
Done with enzyme
Law of Mass Action
If reactants > products then reaction goes forward
If products > reactants then reaction can go backwards
*Only if reaction is reversible
Chemical Reactions
Activation is the energy needed for the reaction to occur
Enzyme
Lower the activation energy
Acts as a catalyst
Reusable
Binds to substrate
Has optimum temperature and pH
Substrate
Reactant an enzyme acts on
Active Site
Where substrate binds
Competitive Inhibitor
Binds to active site of enzyme (competes with enzyme)
Noncompetitive Inhibitor
Binds to another part of an enzyme, changing the function
Metabolic Pathway
Many steps
Uses enzymes as catalysts to lower activation energy
Only need to control one enzyme to turn off entire pathway
Allosteric Control
Activators or inhibitors the control enzyme activity
Control reaction rate
Feedback Inhibition
End product inhibits pathway
Cofactors
Nonprotein enzyme helpers
On/off switches
Zinc, Magnesium, Iron
Can bind to enzyme to create active site
Coenzymes
Organic cofactors
Nad+, FADH (H+ shuttles)
