Enzymes

Enzymes are Proteins Made in the Ribosomes Monomer: Amino Acid Peptide bonds bind amino acids together

Enzymes act as catalysts Speed up chemical reactions by lowering activation energy Activation energy = Energy needed to start a reaction

Enzymes are reusable; they do not get used up Enzymes do not change Enzymes end in –ase EX: Lactase Amylase

Substrates bind to enzymes at the active site Substrate – what the enzyme acts on Active site – where the substrate binds/attaches to

2 ways enzyme and substrate bind Lock & Key Fit – fit perfectly together

2. Induced Fit – enzyme changes shape to fit the substrate

Inhibitor - Prevents function of enzyme (2 types) Competitive – blocks substrate Non-competitive – changes enzyme shape by binding elsewhere

Factors affecting Enzyme activity Denature – decreases function by increasing or decreasing pH or temperature; Not at optimum performance Substrate Saturation – once enzymes are saturated, activity does not increase; too many substrates, not enough enzymes Enzyme Saturation – when enzymes are increased to act on substrates; too many Enzymes, not enough substrates Presence of Inhibitors– when enzymes are changed or reshaped by another protein (inhibitors)

Reviewing Enzymes! http://www.youtube.com/watch?v=NdMVRL4oaUo http://youtu.be/1Pe5a4C6KmY http://youtu.be/CUClhD-lpUA