Enzymes – Online MCQs Test – Biology MCAT

1. Coenzyme can function

In association with a protein

In association with a vitamin

In association with an Apo-enzyme

Independently of the Apo-enzyme

2. The organic prosthetic groups in holoenzymes are called:

Co-enzymes

Holo-group

Co-activators

Co-factors

3. Co-enzymes include:

Manganese

Flavin mononucleotide

Acylglycerol

Phospholipids

4. If the non-protein part is covalently bonded to enzyme, it is known as a:

Coenzyme

Prosthetic group

Co-factor

Holoenzyme

5. A cofactor made of inorganic ion which is detachable is called

Activator

Coenzyme

Prosthetic group

Cofactor

6. Decarboxylases and Dehydratases, are enzymes included in class:

Lyases

Hydrolases

Ligases

Transferase

7. The charge and shape of the active site is formed by:

Allosteric site

Globular shape

Amino acids

Cofactor

8. “When the product is in abundance, it binds competitively with enzyme’s active site, as the product is used up, more product can be produced”, this is an example of:

Feed-back Inhibition

Competitive Inhibition

Non-competitive Inhibition

Activation

9. Non-competitive inhibitor is one which:

Competes to the active site of enzyme

Binds away from the active site of an enzyme

Normally binds to active site of an enzyme

Binds close the active site of an enzyme

10. The important role play by enzymes during reaction is

no effect on energy of activation of reaction

Maintain energy of activation of reaction

Lower down energy of activation of reaction

Increase energy of activation of reaction

11. Enzymes are useful to plants because.

They are building blocks of chlorophyll.

They are used up in reactions.

They enhance absorption of water and salts.

They are essential for the metabolic processes

12. Synthetases are enzymes included in class:

Hydrolases

Transferase

Lyases

Ligases

13. The inorganic ions which act as a prosthetic group in holoenzymes are called:

Co-factors

Ho a-group

Co-enzymes

Co-activators

14. Regarding factors affecting enzyme activity, which of the following statement is correct?

pH has no effect on enzyme activity.

Substrate and enzyme concentration are directly proportional upto a certain maximum velocity.

Rate of reaction decreases with an increase in enzyme concentration until enzyme saturate.

Substrate and enzyme concentration are inversely proportional upto a certain maximum velocity.

15. Enzyme, Glycosidases is included in class:

Lyases

Transferases

Hydrolases

Ligases

16. Enzyme having different molecular arrangement but similar functions is

Apo-enzyme

HoIo-enzyme

Iso-enzyme

Co-enzyme

17. Who is credited with proposing ‘Lock and Key’ theory?

Emil Fischer

Koshland

Buchner

Summer

18. Any factor that can alter the chemistry an shape of an enzyme can affect us rate of.

Catalysis

Photolysis

Hydrolysis

Activity

19. At low concentration of substrate the reaction rate is directly proportional to the available.

Cofactor

Coenzyme

Enzyme

Substrate

20. Concerning temperature affecting enzyme activity, which of the following statement is correct?

Enzymes are completely destroyed at 50°C

Most enzymes are highly active at 50°C

Most enzymes are highly active at 37°C

Enzymes are temperature-resistant

Enzymes-Medical College Admission Test Preparation Notes