Which of the following is an example of feedback allosteric inhibition?
Відповідь
(A)
Inhibition of the first enzyme in a pathway by the end product.
2
Reliable marker of myocardial infarction is:
Відповідь
(C)
CK-2
3
What is the role of the enzyme, Trypsin?
Відповідь
(C)
Digestion of proteins and polypeptides in the small intestine
4
In feedback inhibition, the end product of a metabolic pathway typically acts as a(n):
Відповідь
(B)
Inhibitor of the first enzyme.
5
What is the role of ATP in some enzyme reactions?
Відповідь
(B)
It provides energy.
6
What is the major clinical application of the enzyme Collagenase?
Відповідь
(B)
Removing dead tissue from wounds
7
Which of the following is NOT a characteristic of enzymes?
Відповідь
(B)
They are consumed in the reaction.
8
What is the name of the model that explains that an enzyme has a rigid shape, like a lock?
Відповідь
(B)
Lock and key model
9
The enzyme useful in the treatment of leukemia is:
Відповідь
(B)
Asparaginase
10
What are the main features of competitive inhibitors?
Відповідь
A
B
C
11
A competitive inhibitor:
Відповідь
(A)
Binds to the active site.
12
Which of the following is NOT an example of an enzyme used in clinical diagnostics?
Відповідь
(D)
Trypsin
13
Which type of enzyme inhibitor binds to a site distinct from the active site and, upon binding, alters the enzyme's conformation and catalytic activity?
Відповідь
(B)
Noncompetitive
14
Which of the following is an example of a mechanism-based inhibitor?
Відповідь
(B)
Penicillin
15
Transaminases enzyme belong to the class:
Відповідь
(B)
Transferases
16
What is the primary function of the enzyme, Amylase?
Відповідь
(C)
Digestion of carbohydrates (starch).
17
What is the role of a catalyst?
Відповідь
(C)
To speed up a reaction without being consumed.
18
Which type of inhibition does not alter the Km value?
Відповідь
(B)
Noncompetitive inhibition
19
Which of the following enzyme levels increases in obstructive jaundice?
Відповідь
C
D
20
Which of the following statements is correct regarding enzyme inhibitors?
Відповідь
A
C
D
21
How does a competitive inhibitor affect the reaction rate?
Відповідь
(D)
It can increase or decrease the rate, depending on the substrate concentration.
22
What does the Lineweaver-Burk plot is used for?
Відповідь
(C)
To determine Vmax and Km values.
23
What is the general role of an isomerase?
Відповідь
(C)
To catalyze the rearrangement of atoms within a molecule.
24
Enzymes may be used as the following, except:
Відповідь
(D)
Nutrients
25
What are the common clinical applications of measuring LDH isoenzymes?
Відповідь
(D)
All of the above
26
How do allosteric enzymes regulate biochemical pathways?
Відповідь
(C)
By being regulated by modulators
27
Which type of inhibitor affects both the Km and Vmax of an enzyme?
Відповідь
(C)
Uncompetitive
28
Which inhibitor type results in a decrease in both the Km and Vmax?
Відповідь
(C)
Uncompetitive inhibitor
29
Which of the following is used in the treatment of some types of leukemia?
Відповідь
(B)
Asparaginase
30
Which enzyme is useful for dissolving fibrin clots?
Відповідь
(C)
Streptokinase
31
Which type of enzyme is involved in the transfer of phosphate groups?
Відповідь
(B)
Transferase
32
The 'lock and key' model explains that the enzyme and substrate:
Відповідь
(A)
Fit perfectly together.
33
What would be the effect of a non-competitive inhibitor on a Lineweaver-Burk plot?
Відповідь
(A)
The y-intercept changes and the x-intercept remains the same.
34
Which of the following enzyme classifications catalyze the formation of bonds with the input of ATP?
Відповідь
(B)
Ligases
35
The Michaelis constant (Km) is:
Відповідь
(C)
The substrate concentration at 1/2 Vmax
36
What is a common clinical application of measuring lipase?
Відповідь
(C)
Diagnosis of pancreatitis
37
What is the role of alkaline phosphatase in clinical diagnosis?
Відповідь
(A)
Diagnosis of liver disease and bone disorders
38
What is the effect of an irreversible inhibitor on an enzyme?
Відповідь
(B)
It permanently inactivates the enzyme.
39
In which type of enzyme inhibition does the inhibitor bind to a site distinct from the active site, but changes the shape of the active site?
Відповідь
(B)
Non-competitive inhibition
40
Enzyme activity in biological systems may be affected by the following:
Відповідь
A
B
C
D
41
Which of the following enzymes is classified as a hydrolase?
Відповідь
(C)
Amylase
42
Liver diagnostic enzyme is:
Відповідь
(C)
Alanine transaminase
43
What does Vmax represent?
Відповідь
(B)
The maximum reaction rate.
44
Which enzyme is elevated in urine in the patient of acute pancreatitis?
Відповідь
(A)
Amylase
45
What is the normal serum value for adult of Alkaline phosphatase (ALP)?
Відповідь
(C)
13 to 100 U/L
46
Which of the following can affect enzyme activity?
Відповідь
A
B
C
D
47
Which enzyme, elevated in serum, is used for diagnosis of acute myocardial infarction?
Відповідь
(B)
Creatine Kinase (CK-MB)
48
Which of the following is a characteristic of uncompetitive inhibitors?
Відповідь
(B)
They bind only to the enzyme-substrate complex.
49
What is the primary function of the enzyme amylase?
