1. Enzymes are chemically classified as:
(A) Lipids
(B) Proteins
(C) Carbohydrates
(D) Nucleic acids
2. The non-protein part of an enzyme required for its activity is called:
(A) Substrate
(B) Inhibitor
(C) Product
(D) Coenzyme
3. The substance upon which an enzyme acts is known as:
(A) Product
(B) Inhibitor
(C) Substrate
(D) Catalyst
4. Enzymes that catalyze oxidation–reduction reactions are called:
(A) Hydrolases
(B) Oxidoreductases
(C) Lyases
(D) Ligases
5. The enzyme that converts milk into curd is:
(A) Pepsin
(B) Lactase
(C) Rennin
(D) Lipase
6. The first enzyme to be discovered was:
(A) Urease
(B) Amylase
(C) Pepsin
(D) Catalase
7. The enzyme amylase breaks down:
(A) Protein
(B) Fat
(C) Starch
(D) Cellulose
8. The optimum pH for most enzymes is around:
(A) 3.0
(B) 5.0
(C) 9.0
(D) 7.0
9. Which enzyme catalyzes the breakdown of hydrogen peroxide?
(A) Catalase
(B) Lipase
(C) Amylase
(D) Pepsin
10. Enzymes that transfer phosphate groups are called:
(A) Phosphatases
(B) Kinases
(C) Hydrolases
(D) Lyases
11. The inactive form of an enzyme is called a:
(A) Apoenzyme
(B) Isoenzyme
(C) Holoenzyme
(D) Proenzyme
12. The enzyme that hydrolyzes proteins is:
(A) Amylase
(B) Lipase
(C) Protease
(D) Catalase
13. Which of the following is not an enzyme?
(A) Insulin
(B) Pepsin
(C) Trypsin
(D) Lipase
14. Enzyme activity is affected by:
(A) pH
(B) Temperature
(C) Substrate concentration
(D) All of these
15. Which enzyme is used in the brewing industry?
(A) Amylase
(B) Urease
(C) Catalase
(D) Oxidase
16. Immobilized enzymes are:
(A) Enzymes fixed on a support material
(B) Enzymes in free solution
(C) Inactive enzymes
(D) Denatured proteins
17. The enzyme used in the production of cheese is:
(A) Lactase
(B) Lipase
(C) Rennin
(D) Amylase
18. Which of the following is a microbial enzyme?
(A) Pepsin
(B) Trypsin
(C) Amylase
(D) Pancreatic lipase
19. Enzyme specificity refers to:
(A) Enzyme’s ability to bind a specific substrate
(B) Enzyme’s chemical composition
(C) Enzyme stability
(D) Enzyme solubility
20. The temperature at which enzyme activity is maximum is called:
(A) Activation temperature
(B) Optimum temperature
(C) Catalytic temperature
(D) Equilibrium temperature
21. Enzymes that catalyze joining of two molecules are:
(A) Lyases
(B) Ligases
(C) Hydrolases
(D) Transferases
22. Which type of inhibition can be reversed by increasing substrate concentration?
(A) Non-competitive
(B) Competitive
(C) Irreversible
(D) Allosteric
23. Enzymes increase the rate of a reaction by:
(A) Increasing temperature
(B) Increasing product concentration
(C) Decreasing activation energy
(D) Altering equilibrium
24. The enzyme used in the conversion of glucose to ethanol is:
(A) Zymase
(B) Amylase
(C) Invertase
(D) Catalase
25. The process of enzyme production by microorganisms is called:
(A) Fermentation
(B) Respiration
(C) Pasteurization
(D) Distillation
26. The most common microorganism used in ethanol fermentation is:
(A) Aspergillus niger
(B) Saccharomyces cerevisiae
(C) Lactobacillus
(D) Streptococcus
27. Lactic acid fermentation is carried out by:
(A) Bacteria
(B) Yeast
(C) Mold
(D) Algae
28. The first step in any fermentation process is:
(A) Aeration
(B) Inoculation
(C) Cooling
(D) Sterilization
29. The main product of alcoholic fermentation is:
(A) Acetic acid
(B) Ethanol
(C) Lactic acid
(D) Citric acid
30. Which gas is released during alcoholic fermentation?
(A) Hydrogen
(B) Carbon dioxide
(C) Oxygen
(D) Nitrogen
31. The term “batch fermentation” means:
(A) Continuous addition of substrate
(B) Continuous product removal
(C) Fermentation with no addition or removal during process
(D) Open system fermentation
32. Continuous fermentation offers:
(A) No advantage
(B) Simpler control
(C) Low yield
(D) Higher productivity
33. Which of the following is a product of microbial fermentation?
(A) Citric acid
(B) Penicillin
(C) Ethanol
(D) All of these
34. Enzyme catalysis follows which model?
(A) Lock and key model
(B) Random fit model
(C) Chain reaction model
(D) None of these
35. The optimum temperature for yeast fermentation is about:
(A) 10°C
(B) 25–30°C
(C) 50°C
(D) 70°C
36. The by-product of fermentation used in baking is:
(A) Lactic acid
(B) Alcohol
(C) CO₂
(D) Butyric acid
37. Which microorganism is used for citric acid production?
(A) Aspergillus niger
(B) Saccharomyces cerevisiae
(C) Lactobacillus
(D) Clostridium
38. Fermenters are made of:
(A) Stainless steel
(B) Iron
(C) Plastic
(D) Wood
39. Enzyme activity can be measured in:
(A) Grams per mole
(B) Moles per gram
(C) Milligrams per liter
(D) Units per liter
40. The enzyme used in the production of glucose syrup is:
(A) Invertase
(B) Amylase
(C) Lipase
(D) Protease
41. Which process produces vinegar?
(A) Alcoholic fermentation
(B) Butyric fermentation
(C) Lactic acid fermentation
(D) Acetic acid fermentation
42. The enzyme that hydrolyzes sucrose into glucose and fructose is:
(A) Invertase
(B) Maltase
(C) Lactase
(D) Sucrase
43. The rate of enzyme-catalyzed reaction depends on:
(A) Substrate concentration
(B) Temperature
(C) pH
(D) All of these
44. Which of the following is used for antibiotic fermentation?
(A) Streptomyces species
(B) Aspergillus species
(C) Lactobacillus species
(D) Bacillus species
45. The process used to grow microorganisms under controlled conditions is called:
(A) Incubation
(B) Fermentation
(C) Pasteurization
(D) Cultivation
46. The enzyme that breaks lipid into fatty acids and glycerol is:
(A) Amylase
(B) Pepsin
(C) Lipase
(D) Cellulase
47. The rate of fermentation increases with:
(A) No oxygen supply
(B) High substrate only
(C) Low pH only
(D) Optimum temperature and pH
48. Which vitamin is produced by microbial fermentation?
(A) Vitamin D
(B) Vitamin A
(C) Vitamin B12
(D) Vitamin K
49. The term “aerobic fermentation” refers to:
(A) Anaerobic reaction
(B) Fermentation with oxygen supply
(C) Only chemical oxidation
(D) Enzyme denaturation
50. The enzyme that catalyzes conversion of starch to glucose is:
(A) Lactase
(B) Invertase
(C) Glucoamylase
(D) Maltase