1. The atoms in the

of the

attract

very specific
molecules.
2. Like a key inside a lock,

the

is a perfect fit for the

.

3. The catalyzed reaction
changes the

into

, and

releases them for use by the organism.
active site
substrate
enzyme
products
pH
Reaction rates increase as pH nears the optimum level for an enzyme. Above/below this pH, enzyme function is disrupted and reaction rates decrease.
Temperature
Reaction rates generally increase at higher temperatures, but only up to the optimum temperature for an enzyme. At temperatures above the optimum, reaction rates decrease as enzymes lose their shape or denature.
Presence of Inhibitors or Activators
Reaction rates increase in the presence of activators and decrease in the presence of inhibitors.
Enzyme and Substrate Concentration
Reaction rates increase with increased amounts of enzyme or substrate, but only up to the point at which all of the enzyme molecules are bound to substrate.