Enzymes – Online MCQs Test – Biology MCAT

1. Fischer in 1898 proposed:

Induce Fit Theory

Key-Lock Theory

Enzyme Lock Theory

Catalyst Fit Theory

2. Co-factors include:

Flavin mononucleotide

Phospholipids

Magnesium

Acylglycerol

3. Which of the following is not an attribute of enzymes?

They are specific in nature.

They are proteinaceous in nature.

They are used up in reactions.

They speed up the rate of biochemical reactions.

4. If enzyme concentration is low than substrate, pH and temperature values are equal to requirement then which of the following will increase rate of reaction.

Increase in pH

Increase in concentration of substrate

Increase in temperature

Increase in concentration of enzyme

5. An enzyme can be synthesized by chemical bonding together molecules of

Carbohydrates

CO₂

Lipases

Amino acids

6. Enzymes are classified into _________classes:

Six

Four

Three

Five

7. Co-enzymes include:

Flavin mononucleotide

Phospholipids

Manganese

Acylglycerol

8. Enzymes are basically or all enzymes contain

Sugars

Vitamins

Proteins

Fats

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

Coenzyme

Enzyme

Substrate

Cofactor

10. Synthetases are enzymes included in class:

Hydrolases

Ligases

Lyases

Transferase

11. Penicillin blocks the active site of an enzyme that many bacteria use for:

Synthesis of proteins

ATP hydrolysis

Cellular respiration

Synthesis of cell-wall

12. Which statements are correct for all enzymes?

1, 2, 3 and 4

2 and 4 only

1, 2 and 3 only

1 and 4 only

13. Coenzyme can function

Independently of the Apo-enzyme

In association with a vitamin

In association with an Apo-enzyme

In association with a protein

14. The important role play by enzymes during reaction is

Increase energy of activation of reaction

Maintain energy of activation of reaction

Lower down energy of activation of reaction

no effect on energy of activation of reaction

15. Non-protein part of an enzyme is Known as

Holoenzyme

All of the above

Apoenzyme

Coenzyme

16. Regarding nature of enzymes, which one of the following is correct?

Amylase is an enzyme which entirely consists of protein.

Enzymes are modified lipids.

Simple enzyme consists of protein and non-protein part.

Conjugated enzyme consists of non-protein part.

17. Class hdyrolases includes:

Epimerase

Phosphatase

Hydroxylase

Oxidase

18. All of the following are correct about enzymes EXCEPT

They are assisted by vitamins and minerals

They denature at high temperatures

They are proteins

The mechanism by which enzymes work is known as lock and key

19. Blocking of active site of an enzyme temporarily is a kind of:

Non reversible

Feedback inhibition

Competitive inhibition

Non-competitive inhibition

20. The prosthetic group (metallic cofactor) of various respiratory enzymes is

Enzymes-Medical College Admission Test Preparation Notes