Enzymes and Their Functions

What is the primary role of enzymes in chemical reactions?

• To alter the energy of the reactants

• To consume the reactants

• To speed up the reaction

• To change the products of the reaction

Which term is synonymous with activation energy?

• Potential energy

• Kinetic energy

• Free energy of activation

• Thermal energy

What happens to enzymes after they catalyze a reaction?

• They remain unchanged

• They change their shape permanently

• They are consumed by the reaction

• They become inactive

How do enzymes affect the activation energy of a reaction?

• They decrease it

• They eliminate it

• They increase it

• They do not affect it

Why can't we just add heat to speed up reactions instead of using enzymes?

• Heat is not effective in speeding up reactions

• Heat denatures proteins and is not specific

• Heat is too expensive

• Heat slows down reactions

What is the active site of an enzyme?

• The part where the enzyme is produced

• The part where the substrate binds

• The part that changes shape permanently

• The part that gets consumed

What is formed when an enzyme and a substrate bind together?

• A new substrate

• A new enzyme

• An enzyme-substrate complex

• A covalent bond

Which model describes how enzymes change shape to fit substrates?

• Rigid fit model

• Induced fit model

• Substrate fit model

• Lock and key model

How do enzymes provide a microenvironment for reactions?

• By forming a pocket with specific conditions

• By consuming the reactants

• By changing the temperature

• By altering the substrate permanently

What is the main function of enzymes in biological systems?

• To consume the substrates

• To change the products of reactions

• To lower the activation energy

• To increase the energy of reactants