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