BIOCATALYSIS

Which of the following statements regarding enzyme is TRUE

• Enzyme decreases the free energy change of a reaction

• Enzyme changes the direction of chemical reaction

• Enzyme increase rate of reaction

• Enzyme prevents changes in substrate concentration

An enzyme catalyses a reaction by …

• lowering the energy of activation of a reaction

• supplying the energy to speed up a reaction.

• lowering the free energy of a reaction.

• changing the equilibrium of a spontaneous reaction.

What is the active site of an enzyme?

• A region that binds allosteric regulators of the enzyme

• A region that binds the products of the catalytic reaction

• A region that is inhibited by the presence of a coenzyme or a cofactor

• A region that is involved in the catalytic reaction of the enzyme

Zinc, an essential trace element for most organisms, is present in the active site of enzyme carboxypeptidase. The zinc most likely functions as

• a cofactor necessary for enzyme activity

• a competitive inhibitor of the enzyme

• a non-competitive inhibitor of the enzyme

• a coenzyme derived from a vitamin

Watch the animation and identify the hypothesis involved

• Lock and Key hypothesis

• Induced Fit hypothesis

• Enzyme-Substrate hypothesis

NAD+ is the example of

• metal ions

• coenzyme

• prosthetic group

What is structure A?

• Substrate
• Active site
• Enzyme
• Products

Tags

NGSS.MS-LS1-7

How do enzymes speed up chemical reaction?

• Increasing activation energy
• Decreasing activation energy
• Increasing deactivation energy
• Decreasing deactivation energy

In the diagram, what is letter A? 

• product
• substrate
• enzyme-substrate complex
• active site

what reduces the productivity of enzymes by blocking substrates from entering active sites?

• non competitive inhibitors

• competitive inhibitors

• coenzymes

• cofactors