Energy, ATP, and Enzymes


Energy - the ability to do work, that is, to move matter against opposing forces such as gravity and friction

Thermodynamics - the study of energy transformation Free Energy - the portion of a system's energy the can perform work Exergonic Reaction - a process with a net release of free energy Endergonic Reaction - a process which absorbs free energy from the surroundings Energy Coupling - the use of an exergonic process to drive and endergonic process Types of Cellular Work

Useful and much more detailed links


ATP - Power To Drive Cellular Work

ATP - Adenosine triphosphate - a close relative to Adenine, a nucleotide found in DNA.

Enzymes and Chemical Reactions

Catalyst -  a chemical agent that changes the state of a reaction without being consumed in the reaction
Substrate - reactants
Intermediates - compounds formed between initial reactants & products
Products - products
Cofactors- helpers for enzymes (carry e-)
Energy Carriers - sources of quick energy (ATP)

Enzymes are protein catalysts

How Energy Relates to Reactions



Any reaction requires some energy to overcome the activation energy barrier


Enzymes are Substrate Specific

The Catalytic Cycle of an Enzyme A Cell's Physical and Chemical Environment Affect Enzyme Activity

The Control of Metabolism In many cases, the molecules that naturally regulate enzyme activity behave like reversible noncompetitive inhibitors