Quick Biochemistry - Enzymes (Section 11)
1
The 'Lock and Key' model of enzyme action was theorized by
2
Which of the following is a component of a coenzyme?
3
The structure of an enzyme, and its resulting function, can be temporarily modified by
4
Which of the following control mechanisms utilizes a reversible covalent adjustment to the enzyme?
Answer(A)
Phosphorylation of ser-OH on the enzyme
6
An enzyme facilitates a chemical reaction by
Answer(A)
Decreasing the required energy for activation
7
In most metabolic sequences, all necessary enzymes are organized within a
8
An enzyme that transforms an aldose sugar into a ketose sugar would be categorized as a
9
The primary role of an enzyme is to
Answer(B)
Alter the speed of chemical reactions
10
In which type of enzyme reaction might water be added to a C-C double bond without breaking the bond?
11
How do enzymes affect reaction rates?
Answer(B)
By lowering the activation energy
12
What part of an enzyme is directly involved in substrate binding?
13
What structural characteristic do allosteric enzymes possess?
Answer(A)
Multiple protein subunits
14
Which conditions can be identified using isoenzymes of lactate dehydrogenase?
Answer(D)
Both heart and liver issues
15
How many main categories of enzymes did the IUB classify?
16
Which enzyme was the first to be isolated, purified, and crystallized from Jack bean (Canavalia) in 1926?
17
Who proposed that enzymes are composed of protein?
18
Which factor regulates feedback inhibition of enzyme activity?
Answer(C)
The end products of the reaction
19
What enzyme catalyzes the conversion of glucose to glucose-6-phosphate?
20
Why are enzymes needed in small amounts?
Answer(D)
All of the above are correct
21
What term describes an organic molecule that binds to an enzyme and is crucial for its function?
22
The duration of enzyme-catalyzed reactions is typically measured in
23
Enzymes can speed up a reaction by a factor of up to
24
Where within a plant are enzymes found?
26
Within a holoenzyme, what describes a cofactor (prosthetic group)?
Answer(B)
Accessory non-protein substance attached firmly
27
Which protein exhibits both structural and enzymatic properties?
28
In what way do enzymes differ from other catalysts?
29
What common characteristic unites enzymes, vitamins, and hormones?
30
Why do dry seeds withstand higher temperatures compared to germinating seeds?
Answer(A)
Hydration is essential for making enzymes sensitive to temperature
31
From which vitamin are the coenzymes FMN and FAD derived?
32
Which observation supports the template/lock and key model of enzyme action?
Answer(D)
Substances similar to the substrate hinder enzyme activity
33
What is formed when an apoenzyme combines with a coenzyme?
34
What type of enzyme inhibition occurs when a substance, similar in structure to the substrate, binds to the enzyme?
35
What is the effect of an enzyme on a chemical reaction?
Answer(D)
Reduced activation energy
36
Which factor regulates feedback inhibition of an enzyme?
Answer(C)
The end product of the reaction
37
What is a coenzyme typically composed of?
38
Which enzyme is essential for genetic engineering techniques?
39
Which statement does NOT accurately describe a characteristic of inorganic catalysts compared to enzymes?
Answer(B)
Inorganic catalysts require specific conditions that enzymes do not
40
Who proposed the lock and key model of enzyme action?
41
In a biochemical pathway, what process exemplifies feedback inhibition?
Answer(A)
How does glucose-6-phosphate affect hexokinase activity?
42
In the context of enzyme kinetics, what does the term 'feedback' primarily describe?
Answer(B)
How the end product influences the rate of a reaction
43
What is the primary function of allosteric inhibition?
44
In certain enzymatic reactions, what is the smallest possible ratio of enzyme molecules to substrate molecules?
45
Which coenzyme includes Vitamin B?
46
In enzyme kinetics, what substrate concentration is associated with the K value?
47
In an enzyme, which part combines with a non-protein component to create a functional enzyme?
48
Which scientist was awarded a Nobel Prize in 1978 for their contributions to the field of enzymes?
49
In a cell, where does the synthesis of enzymes primarily occur?
50
Why does fruit left out in the open become bitter after a couple of hours?
Answer(D)
Due to contamination by bacterial enzymes
