9700 B3 Key words

A specific region on an enzyme where the substrate binds and the reaction takes place.

• Action site

• Allosteric site

• Active site

• Prosthetic group

An enzyme that catalyses the extracellular breakdown of starch.

• Amylose

• Amylase

• Pepsin

• Trypsin

An enzyme that catalyses the intracellular breakdown of hydrogen peroxide into oxygen and water.

• Catalyse

• Catalase

• Calatase

• Amylase

A substance that increases the rate of reaction, often by offering an alternative reaction pathway with a lower activation energy. It is unchanged at the end of the reaction.

• Catalyst

• Reactant

• Product

• Substrate

A light-sensitive device that measures the absorbance of transmission of certain wavelengths of light by a solution. Can be used to investigate the rate of a reaction that involves colour changes.

• Calorimeter

• Colorimeter

• Colourimeter

• Caloriemeter

A molecule which binds to the active site of an enzyme and prevents the substrate from binding.

• Competitive inhibitor

• Non-competitive inhibitor

• reversible inhibitor

• irreversible inhibitor

A globular protein molecule that acts as a biological catalyst and increases the rate of biochemical reactions. Some work intracellularly and others work extracellularly.

• Catalyst

• Enzyme

• Enzyme-substrate complex

• Substrate

The temporary complex formed when the substrate binds to the active site of the enzyme.

• enzyme-substrate complex

• holozyme

• enzyme-product complex

• enzyme-substrate product

An enzyme that is secreted by cells and functions outside of cells, e.g. amylase.

• globular enzyme

• intracellular enzyme

• extracellular enzyme

• intercellular enzyme

Enzymes which are attached to an inert, insoluble material over which the substrate passes and the reaction takes place.

• static enzymes

• immobilised enzymes

• attached enzymes

• beaded enzymes