300 + Interview Questions in GENERAL QA IN ENZYMES

1.	In extra hepatic tissues, one mechanism for utilization of acetoacetate involves (A) Malonyl-CoA (B) Succinyl-CoA (C) Propionyl-CoA (D) Acetyl-CoA
Answer» (B) Succinyl-CoA

Discussion

2.	Essential fructosuria is characterized by the lack of the hepatic enzyme: (A) Phosphohexose isomerase (B) Aldalose A (C) Aldolase B (D) Fructokinase
Answer» (D) Fructokinase

Discussion

3.	Vitamin deficiency that causes fatty liver includes all except (A) Vitamin E (B) Pyridoxine (C) Retionic acid (D) Pantothenic acid
Answer» (C) Retionic acid

Discussion

4.	Pantothenic acid acts on (A) NADP (B) NADPH (C) FAD (D) CoA
Answer» Pantothenic acid acts on NADPH.

Discussion

5.	Pyruvate dehydrogenase activity is inhibited by (A) Mercury (B) Zinc (C) Calcium (D) Sodium
Answer» Pyruvate dehydrogenase activity is inhibited by Mercury.

Discussion

6.	In the normal resting state of humans, most of the blood glucose burned as fuel is consumed by (A) Liver (B) Adipose tissue (C) Muscle (D) Brain
Answer» In the normal resting state of humans, most of the blood glucose burned as fuel is consumed by Liver.

Discussion

7.	The function of an enzyme is to (A) Cause chemical reactions that would not otherwise take place (B) Change the rates of chemical reactions (C) Control the equilibrium points of reactions (D) Change the directions of reactions
Answer» (B) Change the rates of chemical reactions

Discussion

8.	An enzyme catalyzes the conversion of an aldose sugar to a ketose sugar would be classified as one of the (A) Transferases (B) Isomerases (C) Oxido reductases (D) Hydrolases
Answer» (A) Transferases

Discussion

9.	This catalyzes formation of CoA derivatives from fatty acid, CoA and ATP: (A) Acyl CoA dehydrogenase (B) Enoyl hydrase (C) β-OH acyl CoA dehydrogenase (D) Thio kinase
Answer» (D) Thio kinase

Discussion

10.	Which one is coenzyme? (A) ATP (B) Vitamin B and C (C) CoQ and CoA (D) All of these
Answer» (D) All of these

Discussion

11.	The co-enzyme containing an automatic hetero ring in the structure is (A) Biotin (B) TPP (C) Sugar Phosphate (D) Co-enzyme
Answer» (C) Sugar Phosphate

Discussion

12.	A coenzyme containing non aromatic hetero ring is (A) ATP (B) NAD (C) FMN (D) Biotin
Answer» A coenzyme containing non aromatic hetero ring is biotin.

Discussion

13.	All the enzymes involved in the synthesis of cholesterol are found in (A) Mitochondria (B) Golgi apparatus (C) Nucleus (D) Endoplasmic reticulum and cytoso
Answer» (D) Endoplasmic reticulum and cytosol

Discussion

14.	Pyruvate is converted into acetyl-CoA by (A) Decarboxylation (B) Dehydrogenation (C) Oxidative decarboxylation (D) Oxidative deamination
Answer» (C) Oxidative decarboxylation

Discussion

15.	For conjugation with many enogenous and exogenous substances before elimination in urine, the uronic acid pathway provides (A) Active glucuronate (B) Gulonate (C) Xylulose (D) Xylitol
Answer» (A) Active glucuronate

Discussion

16.	Name the enzyme that acts both as carboxylase at one time and oxygenase at another time. (A) PEP carboxylase (B) RuBP carboxylase (C) Carbonic anyhdrase (D) None of these
Answer» (B) RuBP carboxylase

Discussion

17.	Which mineral element controls the activity of Nitrate reductase ? (A) Fe (B) Mo (C) Zn (D) Ca
Answer» Fe mineral element controls the activity of Nitrate reductase.

Discussion

18.	The best example of extracellular enzymes (exoenzyme) is (A) Nucleases (B) Digestive enzymes (C) Succinic dehydrogenase (D) None of these
Answer» (C) Succinic dehydrogenase

Discussion

19.	Which enzyme is concerned with transfer of electrons? (A) Desmolase (B) Hydrolase (C) Dehydrogenase (D) Transaminase
Answer» (A) Desmolase

Discussion

20.	Plasma non-functional enzymes are (A) totally absent (B) low concentration in plastic (C) important for diagnosis of several disease (D) All of these
Answer» Correct option (D) All of these Explanation: These enzymes are either totally absent or present at a low concentration in plasma compared to their levels found in tissues. Estimation of plasma non-functional enzymes is important for the diagnosis and prognosis of several diseases.

20.

Plasma non-functional enzymes are (A) totally absent (B) low concentration in plastic (C) important for diagnosis of several disease (D) All of these

Answer»

Correct option (D) All of these

Explanation:

These enzymes are either totally absent or present at a low concentration in plasma compared to their levels found in tissues. Estimation of plasma non-functional enzymes is important for the diagnosis and prognosis of several diseases.

Discussion

21.	The enzymes present in the membrane of mitochondria are (A) Flavoproteins and cytochromes (B) Fumarase and lipase (C) Enolase and catalase (D) Hexokinase and zymase
Answer» (A) Flavoproteins and cytochromes

Discussion

22.	An enzyme in saliva which hydrolyzes starch is (A) Pepsinogen (B) Chymotrysin (C) α-Amylase (D) Malate
Answer» (C) α-Amylase

Discussion

23.	Enzymes functional in cell or mitochondria are (A) Endoenzymes (B) Exoenzymes (C) Apoenzymes (D) Holoenzymes
Answer» (A) Endoenzymes

Discussion

24.	Which enzyme hydrolyses starch? (A) Invertase (B) Maltase (C) Sucrase (D) Diastase
Answer» (D) Diastase

Discussion

25.	In competitive inhibition which of the following kinetic effect is true ? (A) Decreases both Km and Vmax (B) Increases both Km and Vmax (C) Decreases Km without affecting Vmax (D) Increases Km without affecting Vmax
Answer» (D) Increases K_m without affecting V_max

Discussion

26.	In enzyme assays, all the following are kept constant except (A) Substrate concentration (B) Enzyme concentration (C) pH (D) Temperature
Answer» (B) Enzyme concentration

Discussion

27.	The abnormal isoenzyme need not (A) Be an oxidoreductase (B) Have any coenzyme(C) Require ATP(D) Be localized intracellularly (E) Be a catalyst
Answer» (A) Be an oxidoreductase

Discussion

28.	The presence of a non competitive inhibitor (A) Leads to both an increase in the Vmax of a reaction and an increase in Km (B) Leads to a decrease in the observed Vmax (C) Leads to a decrease in Km and Vmax (D) Leads to an increase in Km without affecting Vmax
Answer» (B) Leads to a decrease in the observed V_max

Discussion

29.	In competitive inhibition of enzyme action (A) The apparent Km is decreased (B) The apparent Km is increased (C) Vmax is decreased (D) Apparent concentration of enzyme molecules decreased
Answer» (B) The apparent K_m is increased

Discussion

30.	LDH assays are most useful in diagnosing diseases of the (A) Heart (B) Pancreas (C) Brain (D) Kidney
Answer» LDH assays are most useful in diagnosing diseases of the Heart.

Discussion

31.	How many different proteins may be present in normal LDH? (A) One (B) Two (C) Three (D) Four
Answer» Four different proteins may be present in normal LDH.

Discussion

32.	Trypsin has no action on (A) Hemoglobin (B) Albumin (C) Histone (D) DNA
Answer» Trypsin has no action on DNA.

Discussion

33.	Isoenzymes can be characterized by (A) Proteins lacking enzymatic activity that are necessary for the activation of enzymes (B) Proteolytic enzymes activated by hydrolysis (C) Enzymes with identical primary structure (D) Similar enzymes that catalyse different reaction
Answer» (B) Proteolytic enzymes activated by hydrolysis

Discussion

34.	In non-competitive enzyme action (A) Vmax is increased (B) Apparent km is increased (C) Apparent km is decreased (D) Concentration of active enzyme molecule is reduced
Answer» (C) Apparent k_m is decreased

Discussion

35.	What are zymogens?
Answer» Zymogens, or proenzymes, are enzymes secreted in an inactive form. Under certain conditions a zymogen shifts to the active form of the enzyme. Zymogen secretions in general happen because the enzyme activity can harm the secretory tissue. For example, the pepsinogen secreted by the stomach becomes active under acid pH turning into the enzyme pepsin. Other well-known zymogens are trypsinogen and chymotrypsinogen, enzymes that are secreted by the exocrine pancreas and which become trypsin and chymotrypsin respectively.

35.

What are zymogens?

Answer»

Zymogens, or proenzymes, are enzymes secreted in an inactive form. Under certain conditions a zymogen shifts to the active form of the enzyme. Zymogen secretions in general happen because the enzyme activity can harm the secretory tissue.

For example, the pepsinogen secreted by the stomach becomes active under acid pH turning into the enzyme pepsin. Other well-known zymogens are trypsinogen and chymotrypsinogen, enzymes that are secreted by the exocrine pancreas and which become trypsin and chymotrypsin respectively.

Discussion

36.	Which of the following is a substratespecific enzyme? (A) Hexokinase (B) Thiokinase (C) Lactase (D) Aminopeptidase
Answer» Lactase is a substratespecific enzyme.

Discussion

37.	Coenzymes are required in which of the following reactions? (A) Oxidation-reduction (B) Transamination (C) Phosphorylation (D) All of these
Answer» (D) All of these

Discussion

38.	An increase in LDH-5 enzyme is seen in the following except (A) Acute hepatitis (B) Muscular distrophies (C) Breast carcinoma (D) Pulmonary embolism
Answer» (D) Pulmonary embolism

Discussion

39.	Coenzymes combine with (A) Proenzymes (B) Apoenzymes (C) Holoenzymes (D) Antienzymes
Answer» (B) Apoenzymes

Discussion

40.	Multiple forms of the same enzymes are known as (A) Zymogens (B) Isoenzymes (C) Proenzymes (D) Pre-enzymes
Answer» (B) Isoenzymes

Discussion

41.	The chemical forces that bind most coenzymes and substrates to enzymes such as LDH are (A) Hydrogen bonds (B) Peptide bonds (C) Coordinate bonds (D) Covalent bonds
Answer» (D) Covalent bonds

Discussion

42.	Proenzymes: (A) Chymotrysinogen (B) Pepsinogen (C) Both (A) and (B) (D) None of these
Answer» Correct option (B) Pepsinogen Explanation: Some enzymes are synthesized in an inactive form which are referred to as proenzymes (or zymogens). They undergo irreversible modification to produce active enzymes. e.g., proenzymes – chymotrypsinogen and pepsinogen are respectively converted to chymotrypsin and pepsin.

42.

Proenzymes: (A) Chymotrysinogen (B) Pepsinogen (C) Both (A) and (B) (D) None of these

Answer»

Correct option (B) Pepsinogen

Explanation:

Some enzymes are synthesized in an inactive form which are referred to as proenzymes (or zymogens). They undergo irreversible modification to produce active enzymes. e.g., proenzymes – chymotrypsinogen and pepsinogen are respectively converted to chymotrypsin and pepsin.

Discussion

43.	Inactive precursors of enzymes are known as (A) Apoenzymes (B) Coenzymes (C) Proenzymes (D) Holoenzymes
Answer» (C) Proenzymes

Discussion

44.	An important finding in Tay-sach’s disease is (A) Renal failure (B) Accumulation of gangliosides in brain and spleen (C) Cardiac failure (D) Anemia
Answer» (B) Accumulation of gangliosides in brain and spleen

Discussion

45.	Example of an extracellular enzyme is (A) Lactate dehydrogenase (B) Cytochrome oxidase (C) Pancreatic lipase (D) Hexokinase
Answer» (C) Pancreatic lipase

Discussion

46.	Daily urinary urobilinogen excretion in adult men is (A) 0–4 mg (B) 5–8 mg (C) 9–12 mg (D) 13–20 mg
Answer» Daily urinary urobilinogen excretion in adult men is 0–4 mg.

Discussion

47.	The highest energy level is present amongst the following in (A) 1, 3-Biphosphoglycerate (B) Creatine phosphate (C) Carbamoyl phosphate (D) Phosphoenol pyruvate
Answer» (D) Phosphoenol pyruvate

Discussion

48.	Different isoenzymes of an enzyme have the same (A) Amino acid sequence (B) Michaelis constant (C) Catalytic activity (D) All of these
Answer» (C) Catalytic activity

Discussion

49.	A high-energy phosphate among the following is (A) Glucose-6-phosphate (B) Glucose-1-phosphate (C) 1, 3-Biphoglycerate (D) All of these
Answer» (C) 1, 3-Biphoglycerate

Discussion

50.	From the pentapeptide, phe-ala-leu-lysarg, phenylalanine residue is split off by (A) Trypsin (B) Chymotrypsin (C) Aminopeptidase (D) Carboxypeptidase
Answer» (C) Aminopeptidase

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In extra hepatic tissues, one mechanism for utilization of acetoacetate involves (A) Malonyl-CoA (B) Succinyl-CoA (C) Propionyl-CoA (D) Acetyl-CoA

Essential fructosuria is characterized by the lack of the hepatic enzyme: (A) Phosphohexose isomerase (B) Aldalose A (C) Aldolase B (D) Fructokinase

Vitamin deficiency that causes fatty liver includes all except (A) Vitamin E (B) Pyridoxine (C) Retionic acid (D) Pantothenic acid

Pantothenic acid acts on (A) NADP (B) NADPH (C) FAD (D) CoA

Pyruvate dehydrogenase activity is inhibited by (A) Mercury (B) Zinc (C) Calcium (D) Sodium

In the normal resting state of humans, most of the blood glucose burned as fuel is consumed by (A) Liver (B) Adipose tissue (C) Muscle (D) Brain

The function of an enzyme is to (A) Cause chemical reactions that would not otherwise take place (B) Change the rates of chemical reactions (C) Control the equilibrium points of reactions (D) Change the directions of reactions

An enzyme catalyzes the conversion of an aldose sugar to a ketose sugar would be classified as one of the (A) Transferases (B) Isomerases (C) Oxido reductases (D) Hydrolases

This catalyzes formation of CoA derivatives from fatty acid, CoA and ATP: (A) Acyl CoA dehydrogenase (B) Enoyl hydrase (C) β-OH acyl CoA dehydrogenase (D) Thio kinase

Which one is coenzyme? (A) ATP (B) Vitamin B and C (C) CoQ and CoA (D) All of these

The co-enzyme containing an automatic hetero ring in the structure is (A) Biotin (B) TPP (C) Sugar Phosphate (D) Co-enzyme

A coenzyme containing non aromatic hetero ring is (A) ATP (B) NAD (C) FMN (D) Biotin

All the enzymes involved in the synthesis of cholesterol are found in (A) Mitochondria (B) Golgi apparatus (C) Nucleus (D) Endoplasmic reticulum and cytoso

Pyruvate is converted into acetyl-CoA by (A) Decarboxylation (B) Dehydrogenation (C) Oxidative decarboxylation (D) Oxidative deamination

For conjugation with many enogenous and exogenous substances before elimination in urine, the uronic acid pathway provides (A) Active glucuronate (B) Gulonate (C) Xylulose (D) Xylitol

Name the enzyme that acts both as carboxylase at one time and oxygenase at another time. (A) PEP carboxylase (B) RuBP carboxylase (C) Carbonic anyhdrase (D) None of these

Which mineral element controls the activity of Nitrate reductase ? (A) Fe (B) Mo (C) Zn (D) Ca

The best example of extracellular enzymes (exoenzyme) is (A) Nucleases (B) Digestive enzymes (C) Succinic dehydrogenase (D) None of these

Which enzyme is concerned with transfer of electrons? (A) Desmolase (B) Hydrolase (C) Dehydrogenase (D) Transaminase

Plasma non-functional enzymes are (A) totally absent (B) low concentration in plastic (C) important for diagnosis of several disease (D) All of these

The enzymes present in the membrane of mitochondria are (A) Flavoproteins and cytochromes (B) Fumarase and lipase (C) Enolase and catalase (D) Hexokinase and zymase

An enzyme in saliva which hydrolyzes starch is (A) Pepsinogen (B) Chymotrysin (C) α-Amylase (D) Malate

Enzymes functional in cell or mitochondria are (A) Endoenzymes (B) Exoenzymes (C) Apoenzymes (D) Holoenzymes

Which enzyme hydrolyses starch? (A) Invertase (B) Maltase (C) Sucrase (D) Diastase

In competitive inhibition which of the following kinetic effect is true ? (A) Decreases both Km and Vmax (B) Increases both Km and Vmax (C) Decreases Km without affecting Vmax (D) Increases Km without affecting Vmax

In enzyme assays, all the following are kept constant except (A) Substrate concentration (B) Enzyme concentration (C) pH (D) Temperature

The abnormal isoenzyme need not (A) Be an oxidoreductase (B) Have any coenzyme(C) Require ATP(D) Be localized intracellularly (E) Be a catalyst

The presence of a non competitive inhibitor (A) Leads to both an increase in the Vmax of a reaction and an increase in Km (B) Leads to a decrease in the observed Vmax (C) Leads to a decrease in Km and Vmax (D) Leads to an increase in Km without affecting Vmax

In competitive inhibition of enzyme action (A) The apparent Km is decreased (B) The apparent Km is increased (C) Vmax is decreased (D) Apparent concentration of enzyme molecules decreased

LDH assays are most useful in diagnosing diseases of the (A) Heart (B) Pancreas (C) Brain (D) Kidney

How many different proteins may be present in normal LDH? (A) One (B) Two (C) Three (D) Four

Trypsin has no action on (A) Hemoglobin (B) Albumin (C) Histone (D) DNA

Isoenzymes can be characterized by (A) Proteins lacking enzymatic activity that are necessary for the activation of enzymes (B) Proteolytic enzymes activated by hydrolysis (C) Enzymes with identical primary structure (D) Similar enzymes that catalyse different reaction

In non-competitive enzyme action (A) Vmax is increased (B) Apparent km is increased (C) Apparent km is decreased (D) Concentration of active enzyme molecule is reduced

What are zymogens?

Which of the following is a substratespecific enzyme? (A) Hexokinase (B) Thiokinase (C) Lactase (D) Aminopeptidase

Coenzymes are required in which of the following reactions? (A) Oxidation-reduction (B) Transamination (C) Phosphorylation (D) All of these

An increase in LDH-5 enzyme is seen in the following except (A) Acute hepatitis (B) Muscular distrophies (C) Breast carcinoma (D) Pulmonary embolism

Coenzymes combine with (A) Proenzymes (B) Apoenzymes (C) Holoenzymes (D) Antienzymes

Multiple forms of the same enzymes are known as (A) Zymogens (B) Isoenzymes (C) Proenzymes (D) Pre-enzymes

The chemical forces that bind most coenzymes and substrates to enzymes such as LDH are (A) Hydrogen bonds (B) Peptide bonds (C) Coordinate bonds (D) Covalent bonds

Proenzymes: (A) Chymotrysinogen (B) Pepsinogen (C) Both (A) and (B) (D) None of these

Inactive precursors of enzymes are known as (A) Apoenzymes (B) Coenzymes (C) Proenzymes (D) Holoenzymes

An important finding in Tay-sach’s disease is (A) Renal failure (B) Accumulation of gangliosides in brain and spleen (C) Cardiac failure (D) Anemia

Example of an extracellular enzyme is (A) Lactate dehydrogenase (B) Cytochrome oxidase (C) Pancreatic lipase (D) Hexokinase

Daily urinary urobilinogen excretion in adult men is (A) 0–4 mg (B) 5–8 mg (C) 9–12 mg (D) 13–20 mg

The highest energy level is present amongst the following in (A) 1, 3-Biphosphoglycerate (B) Creatine phosphate (C) Carbamoyl phosphate (D) Phosphoenol pyruvate

Different isoenzymes of an enzyme have the same (A) Amino acid sequence (B) Michaelis constant (C) Catalytic activity (D) All of these

A high-energy phosphate among the following is (A) Glucose-6-phosphate (B) Glucose-1-phosphate (C) 1, 3-Biphoglycerate (D) All of these

From the pentapeptide, phe-ala-leu-lysarg, phenylalanine residue is split off by (A) Trypsin (B) Chymotrypsin (C) Aminopeptidase (D) Carboxypeptidase