Biology Chapter 7 Entry test MCQs
26. An enzyme that is not protein in nature:
a. Arginase
b. Amylopsin
c. Peptidyl transferase
d. Bam H1
Mechanism 1 of Action of Enzymes
27. ES complex is converted into product by:
a. Catalytic site
b. Co-factor
c. Binding site
d. Coenzyme
28. ————suggested that each enzyme had a particular shape into which the substrate fit exactly.
a. Emil Fischer
b. Koshland
c. Michael Menten
d. Robert Whittaker
29. Allosteric enzymes have major sites.
a. 2
b. 1
c. 4
d. 3
30. According to————model, the active site of enzyme is modified as the substrate interacts with enzyme.
a. Lock and key
b. Induced fit
c. Fluid mosaic
d. Emil Fischer
31. Modified form of Lock and model was proposed by:
a. Fischer
b. Koshland
c. Rosalind Franklin
d. Watson
32. According to Lock and Key model, the enzyme acts as:
a. Can act as both
b. Key
c. Lock
d. None
33. Working of sucrase and maltase can be explained by:
a. Induce fit model
b. Lock and key
c. Both models
d. None
34. With the increase of enzyme concentration in a reaction, more———– is/are available for the substrate.
a. Active sites
b. Binding sites
c. Activation energy
d. Products
35. Lock and key model for enzyme action proposed by Emil Fischer suggests that:
a. Enzymes are restricted to one reaction type
b. Enzymes are unbiased for substrate
c. Enzyme can catalyze variety of reactions
d. Enzymes can modify their active sites
Factors Affecting Rate of Enzyme Action
36. The effect of reversible competitive inhibitor can be neutralized by increasing the concentration of:
a. Enzyme
b. Substrate
c. Inhibitor
d. Activator
37. If the concentration of substrate molecule is higher than the enzymes then rate of reaction would be:
a. Remain constant
b. Increasing
c. Variable
d. Decreasing
38. Optimum pH of enterokinase is:
a. Slightly basic
b. Slightly acidic
c. Highly basic
d. Highly acidic
39. Which of the following properties of amino acids is affected by a change in pH?
a. Reduction of amino acids
b. Oxidation of amino acids
c. lonization of amino acids
d. Atomization of amino acids
40. Change in temperature from 30°C to 40°C in human body will cause:
a. First increase then decreases in rate of reaction
b. Increase in rate of reaction
c. First increase then become constant
d. Decrease in rate of reaction
41. Which of the following factor does not affect the rate of enzyme action?
a. Light intensity
b. Enzymes concentration
c. Temperature
d. Substrate concentration
42. Which one of the following is the optimum pH of pancreatic lipase enzyme?
a. 8.00
b. 7.60
c. 9.70
d. 9.00
44. The temperature that promotes the maximum activity of enzyme is referred as:
a. Optimum temperature
b. Fixed temperature
c. Active temperature
d. Controlled temperature
45. Which type of bonds is mostly affected in an enzyme molecule when there are pH fluctuations?
a. Hydrogen bonds
b. Ionic bonds
c. Peptide bond
d. Disulphide bonds
46. Most enzymes have an optimum temperature of around:
a. 40°C
b. 30°C
c. 20°C
d. 50°C
47. Enzymes which require optimum temperature to be lower than 37° C for their proper functioning are present in:
a. Kidney
b. Liver
c. Stomach
d. Testes
48. Which of the followings statement is correct?
a. All enzymes in human body work at same temperature and same pH
b. All enzymes in human body work at same temperature but different pH
c. All enzymes in human body work at different temperature and different pH
d. All enzymes in human body work at different temperature but same pH
49. Bond sensitive to change in temperature and pH are respectively:
a. lonic, Hydrogen
b. Hydrogen, lonic
c. Covalent, lonic
d. Hydrogen, Covalent
50. The temperature where inactive enzyme becomes active is called:
a. Maximum temperature
b. Optimum temperature
c. Activation temperature
d. Minimum temperature
Enzyme Inhibition
51. The competitive inhibitors have structural similarity with:
a. Binding site
b. Active site
c. Coenzyme
d. Substrate
53. Which of the following type of inhibitor can be neutralize by adding more substrate into reaction?
a. Reversible inhibitor
b. Irreversible inhibitor
c. Irreversible competitive
d. Irreversible non-competitive
54. If molecule can bind to another site of the enzyme rather than the true active site, it is referred as————–
a. Allosteric inhibition
b. Non-competitive inhibitors
c. Irreversible inhibition
d. Competitive inhibitors
55. What is common in both competitive and non-competitive inhibition?
a. Feedback inhibition
b. Irreversible inhibition
c. Non-Reversible inhibition
d. Reversible inhibition
56. A student of chemical engineering mistakenly engulfed the toxic compound “A” which was a potent inhibitor of certain enzyme. He was immediately brought to hospital where the doctor injected intravenously substrate “B” to minimize the toxic effect of compound A. His life was saved from serious damages. The treatment method shows that compound A was a————inhibitors.
a. Competitive reversible
b. Temperature sensitive
c. Non-competitive reversible
d. Irreversible
57. Penicillin, an antibiotic inhibits bacterial growth. It is categorized as:
a. Non-competitive inhibitors
b. Irreversible inhibitors
c. Reversible inhibitors
d. Competitive inhibitors
58. which of the following is not an inhibitor of enzymes?
a. Antibiotics
b. Anti-metabolites
c. ATP
d. Sucrose
59. Heavy metal ions that act as inhibitors(mercury, silver and copper) break———–in enzymes?
a. Hydrogen bonds
b. Peptide bonds
c. Ionic bonds
d. Disulfhide bridge
Classification
60. phosphatases belongs to which group of the following?
a. Hydrolases
b. Lyases
c. Ligase
d. None of the above
61. Cytochrome oxidase are categorized in:
a. Oxidoreductases
b. Transferases
c. Hydrolases
d. Lyases
62. Conversation of glucose 6-phosphate into fructose 6-phosphate is done by:
a. Oxidoreductases
b. Transferases
c. Hydrolases
d. Isomerases