AP Biology- Enzymes

Enzyme

a macromolecule that serves as a catalyst - most are proteins

substrate

the reactant on which an enzyme works

active site

the specific region of an enzyme that binds the substrate and forms the pockets in which a catalyst occurs

catalyst 

a chemical agent that selectively increases the rate of a reaction without being consumed by the reaction (part of it)

activation energy

the amount of energy that a chemical must absorb before a chemical reaction occurs

induced fit

the change in shape of a active site of an enzyme so it binds better to the substrate- caused by substrate entry

reactant 

a starting material in a chemical reaction 

product

a material resulting from a chemical reaction

competitive inhibitor

a substance that reduces the activity of an enzyme by entering the active site in place of the substrate

noncompetitive inhibitor 

reduces activity of enzyme by binding to a location remote from the active site- changes enzyme shape 

allosteric regulation

the binding of a regulatory molecule to a protein at one site that affects the function of a protein at a different site

feedback inhibition

a method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway

denaturation

in proteins it is a process in which a protein loses its native shape due to disruption of weak chemical bonds and interactions

optimal conditions

a specific environmental factors such as temp, pH, and substrate concentration

ATP

an adenine-containing nucleoside triphosphate that releases free energy when phosphate bonds are hydrolyzed- used to drive endergonic reactions

exergonic reaction

a reaction the releases energy, an example is cellular respiration

endergonic reaction

a reaction that adds energy to the reactants, an example is photosynthesis

metabolism

the sum of all chemical reactions in an organism that sustain life, which involves two main categories: catabolism and anabolism.

Anabolic reaction

a reaction that build things, examples are dehydration synthesis, photosynthesis and protein synthesis- a nonspontaneous reaction so something needs to make it happen

catabolic reaction

a reaction that breaks things down examples are hydrolysis and cellular respiration- it is spontaneous

catabolic pathway

breaks down complex molecules into a simpler one releasing energy to power cellular functions, primarily in the form of ATP

cofactor

a nonprotein chemical compound or metabolic ion

coenzymes

organic molecules that assist enzymes in catalyzing reactions