Question

Define an enzyme. How do you differentiate between an enzyme and an ordinary catalyst?

Answer 1

Hint: Enzymes are organic biocatalysts, meaning that they are of biological origin and serve a wide range of important functions in a body. Catalysts are inorganic substances that increase or decrease the rate of a chemical reaction without themselves undergoing any change.

Complete answer: Definition of enzyme: Enzymes are protein molecules which are capable of catalyzing chemical reactions of biological origin without themselves undergoing any change. Therefore, they are known as biocatalysts.

Difference between an enzyme and an ordinary catalyst

S.No.	Enzymes	Catalysts
1.	Enzymes are complex proteins.	Catalysts are simple inorganic molecules.
2.	These are high molecular weight globular proteins.	These are low molecular weight compounds.
3.	An enzyme catalyses a specific reaction of a single or a few substances.	A catalyst can catalyse a wide range of reactions.
4.	They are highly efficient.	They are less efficient.
5.	Enzymes originate in the biological world and operate various biochemical reactions.	Catalysts operate in physical or non-living worlds.
6.	Enzymes work only on specific temperature ranges. They get inactivated at low temperature and denatured at high temperature.	Catalysts are not sensitive to small changes in temperature. They work at high temperatures.
7.	Enzymes work effectively only in a narrow range of pH.	Catalysts are not sensitive to small changes in pH.
8.	The activity of enzymes is regulated by specific substances.	The functioning of catalysts is not regulated by regulator molecules.

Note: Catalyst and enzyme are two substances that increase the rate of a reaction without being changed by the reaction. There are two types of catalysts as enzymes and inorganic catalysts. Enzymes are a type of biological catalysts.