Lecture 7 Flashcards
Metabolism
All of a cells chemical reactions
Anabolism
Require energy to organize cell
Catabolism
Release energy by breakdown of nutrients
Energy
Capacity to cause change or do work
Potential Energy
Stored energy due to position or composition
Kinetic Energy
Energy due to movement
Thermodynamics
Study of energy conversions
Exergonic
Exothermic but in an open system
Endergonic
Energy put into system
Spontaneous
Exergonic, negative ∆G, energy released, catabolism
Non-spontaneous
Endergonic, positive ∆G, energy required, anabolism
Energy Coupling
Energy released by exergonic reactions is used to power endergonic reactions
ATP
Adenosine triphosphate, RNA nucleotide, energy currency, major energy source for cell, potential energy due to position and composition
Enzymes
Biological catalysts, proteins, provide an alternate energy path for a reaction to proceed, regulate exergonic and endergonic reactions
Activation Energy
Energy required for a reaction to proceed
Active Site
Catalytic site, binding site of substrate, associates with substrate via non-covalent bonds (hydrogen bonds or sometimes ionic)
Catalysis
Substrate is converted into products
Induced Fit Model
Slight change to enzyme shape to accommodate substrate, “hand-shake” model
Exogenous Inhibition
Inhibitors come from outside of cell
Competitive Inhibitors
Inhibitors which bind the active site but do not participate in a reaction, can be out-competed by increasing concentration of substrate
Non-competitive Inhibitors
Inhibitors which bind a site that is not the active site (allosteric site), illicites a change in shape which blocks enzyme activity
