UNIT#07 ENZYMES Flashcards
1
Q
If enzymes stop their functions, then biochemical reactions would:
A
Be slowed downs
2
Q
All of the following are true or an enzyme except:
A
Increase the energy of activation
3
Q
Enzymes catalyze all of the following except:
A
Breathing
4
Q
The lower the activation energy, the ____ the reaction will be:
A
Faster
5
Q
Most of the enzymes are:
A
Attached wiht organelees
6
Q
Enzymes related to fatty acids oxidation are present in/at:
A
Mitochondria
(Fatty acid metabolism)
7
Q
Al enzymes are ____.
A
Globular proteins
8
Q
The reactants on which enzymes work are:
A
Substrates
9
Q
What is true about enzymes?
A
No effect on the end product
10
Q
The main difference between catalysts and enzymes is:
A
Catalysts are inorganic while enzymes are organic in nature
11
Q
The type of energy reduced by the enzymes for biological reactions to occur is called the:
A
Activation energy
12
Q
It is false about enzymes:
A
➡All enzymes require a co-factor for proper functioning✅
➡Only a small amount of enzymes is required❌
➡THey work in vitro as well as in vivo conditions❌
➡They lower activation energy❌
13
Q
Biochemically enzymes are:
(all enzymes are globular)
A
Proteins
14
Q
All enzymes are proteins:
A
Globular
15
Q
Three-dimensional globular protein is:
A
Enzymes
16
Q
Which of the following is NOT a globular protein?
A
Increases the rate of reaction
17
Q
Enzymes involved in cellular respiration are found in:
A
Mitochondria
18
Q
Which of the following is an example/s of enzymes attached to membrane systems inside the cell in a specific and orderly arrangement?
A
➡Mitochondira
➡Chloroplast
19
Q
The reaction will proceed faster if the activation energy is?
A
Low
20
Q
The energy required to start a reaction is called?
A
Activation energy
21
Q
An enzyme that requires a biological change in order to become active is called?
A
Zymogen
22
Q
AN enzyme without its cofactor is called:
A
Apoenzyme
23
Q
If the non-protein part of the enzyme is covalently bonded to the enzyme it is known as?
A
Prosthetic group
24
Q
Small organic, the non-protein part that helps in enzyme reactions:
A
Co-factor
25
An activated enzyme made up of a polypeptide with its cofactor is:
Holoenzyme
26
Nicotinamide adenine dinucleotide is an example of:
Co-enzyme
27
Co-enzyme requires:
Vitamins
28
Which of the following form weak linkage with an enzyme?
Co-enzyme
29
Co-factors are divided into groups:
3
30
The substrate binds to a specific region of an enzyme called?
Active site
31
All enzymes are:
Globular proteins
32
What does the active site of the enzyme determine?
Determines by its structure the specificity of an enzyme
33
Enzymes showing substrate specificity are specific to how many substrates?
1
34
Which term is used to refer to an inactive enzyme precursor?
Zymogen
35
Catalysts that increase the rate of biological chemical reactions are called?
Enzymes
36
Which of the following best describes a co-enzyme?
Loosely bonded non-protein part of an enzyme
37
Which statement about enzymes is incorrect?
➡Some of them consist solely o protein with no non-protein part❌
➡They catalyze a chemical reaction without being utilized❌
➡They without their cofactor are called apoenzyme❌
➡All enzymes are fibrous proteins ✅
38
The active form of an enzyme:
holoenzyme
39
A cofactor made of inorganic on which is detachable is called
Activator
40
Enzymes are globular proteins because
They have a tertiary structure
41
A small organic, non-protein molecule that carries chemical groups between enzymes are:
Co-enzyme
42
Biological molecules which catalyze a biochemical reaction and remain unchanged after completion of the reaction are called:
Enzymes
43
Enzymes bind with chemical reactants known as:
Substrate
44
Which of the following vitamin acts as a coenzyme
➡Vitamin B
➡Vitamin B2
45
If the non-protein part of the enzyme is covalently bonded to the enzyme it is known as?
Prosthetic group
46
The enzyme reacts with the substrate to form:
Product
47
Enzymes are ____ in nature:
Proteins
48
Which type of bond is never formed when the substrate fits into the active site of the enzyme
Hydrophobic interaction
49
The mechanism of enzyme activation is referred to as:
Catalysis
50
The specificity of enzyme structure depends upon:
Active site
51
The catalytic activity takes place at:
Active site
52
Which statement about the active sites is not true?
➡Acitve site is a spherical shape❌
➡Active site is non-specific✅
➡Active site contains few amino acids❌
➡Active site converts the substrate into product❌
53
Type of bond present between enzyme and prosthetic group:
Covalent
54
Which one forms the raw material for coenzymes?
Vitamins
55
The reaction takes place in a small part of the enzyme is called:
Active site
56
Coenzymes are closely related to;
Vitamins
57
The atoms, groups of atoms and molecules that join with enzymes that alter their shape and make them functional
Co-factors
58
If the cofactor is a non-protein like a metallic ion, it is referred to as a:
Activator
(Metallic ion)
59
The non-protein part which is organic in nature and detachable is called:
Coenzyme
60
The function of succinate dehydrogenase is aided by:
FAD+
61
Prosthetic groups are:
Organic molecules
62
All coenzymes are derived from:
Vitamins
63
A co-factor tightly bound to the enzyme on a permanent basis is called:
Prosthetic Group
64
An enzyme is required Mg+2 to catalyze the substrate. The Mg+2 is the best identified as:
Activator
65
Which of the following comprises inorganic ions?
Activators
66
A non-protein part essential for the proper functioning of the enzyme is called:
Co-factor
67
An enzyme that is non-protein in nature:
Peptidyl transferase
➡Ribozyme(made up of RNA)
68
An enzyme and substrate react through definite charge-bearing sites.
Active site
69
The active site of an enzyme:
Determine by its structure, the specificity of the enzyme
70
The specificity of the enzyme is due to its _____.
Configuration
71
The lock and key model was proposed by:
Emil Fischer
72
According to the Lock and Key model, the active site is:
Rigid structure
73
The lock and key model of enzyme action were proposed by:
Emil Fischer
74
The complex that forms when a substrate binds to the enzyme is called;
Enzyme-substrate complex
75
Who proposed the lock and key model of enzyme activity?
Emil Fischer
76
In the lock and key model of enzyme activity, the substrate acts as the;
Lock
77
Do enzymes work by which of the following?
Reducing the activation energy
78
How many models are present for enzyme-substrate complex or reaction?
2
79
Which statement is incorrect about the lock and key model?
➡Specific enzyme can transform only a specific substrate❌
➡Ative site of an enzyme is a non-flexible structure❌
➡Active site does not change before during or even after reaction❌
➡It explains the mechanism of every chemical reaction✅
80
Which types are never formed when a substrate fits into the active site of an enzyme?
Covalent linkages
81
Koshland in 1959 proposed the modified form of which the following?
Induced fit model
82
The induced fit model was introduced by Koshland in which of the following year?
1959
83
The lock and key model was proposed by:
Fischer
84
Which of the following is false concerning enzymes?
Enzymes increase both the forward rate and reverse rate of a reaction
85
A number of substrate molecules converted into the product by one molecule of enzyme active site per unit time is called:
Turnover number
86
According to the induced fit model, what happens when an enzyme-substrate complex is formed?
The contact between the substrate and the enzyme causes a change in the shape of the active site
87
What effect do enzymes have on the activation energy of a reaction?
Decrease
88
While bound to the active site, the substrate is converted into which of the following?
Product of reaction
89
The primary function of co-factors is to?
Assist in enzyme activity
90
In enzyme catalytic reaction the substrate is first converted to a high energy state called?
Transition state
91
Allosteric enzymes consist of multiple:
Polypeptide chains
92
The function of enzymes includes all of the following:
Shifting substrates into more favourable positions in the active site
93
ES complex is converted into the product by:
Catalytic site
94
____ suggested that each enzyme had a particular shape into which the substrate fits exactly.
Amil Fischer
95
Allosteric enzymes have ____ major sites.
2
96
According to the ____ model, the active site of the enzyme is modified as the substrate interacts with the enzyme.
Induced fit model
97
A modified form of the Lock and model was proposed by:
Koshland
98
According to Lock and Key model, the enzymes acts as:
Key
99
The working of sucrase and maltase can be explained by:
Lock and Key Model
100
With the increase of enzyme concentration in a reaction, more ____ is/are available for the substrate.
Binding sites
101
The lock and key model for enzyme action proposed by Emil Fischer suggest that:
Enzymes are restricted to one reaction type
102
The effect of a reversible competitive inhibitor can be neutralized by increasing the concentration of:
Substrate
103
If the concentration of the substrate molecule is higher than the enzymes then the rate of reaction would be:
Remain constant
104
Optimum pH of enterokinase is:
Slightly acidic
(pH= 5.50)
105
Which of the following properties of amino acids is affected by a change in pH?
Ionization of amino acids
106
Change in tempertue from 30C to 40 C in human body will cause:
First increase then decreases the rate of reaction
107
Which of the following factor does not affect the rate of enzyme acton?
Light intensity
108
Which one of the following is the optimum pH of pancreatic lipase enzyme?
➡7.60=Catalase
➡9.00=Pancreatic Lipase
➡8.00=Chymotrypsin
➡9.70=Arginase
109
The temperature that promotes the maximum activity of enzyme is referred as:
Optimum Temperature
110
Which type of bond is mostly affected in an enzyme molecule when there is pH fluctuation?
Ionic Bonds
111
Most enzymes have an optimum temperature of around:
40C
112
Enzymes which require optimum temperature to be lower than 37C for their proper functioning are present in:
Testes
(Spermatogenesis takes place at 35C)
113
Which of the following statement is correct?
All enzymes in human body work at same temperature but different pH
114
Bond sensitive to change in temperatre and pH are respectively:
➡Hydrogen (Temperature)
➡Ionic (pH)
115
The tempeature where inactive enzyme becomes active is called:
Minimum Temperature
116
The rate of an enzyme-controlled reaction increases rapidly if the amount of enzyme is doubled in the presence of an unlimited substrate concentration. This is due to:
Number of active sites increase
117
THe optimum tempearture for enzymes to work at maximum rate in human is:
37C
118
Enzymes lower down the energy of:
Activation
119
Optimum pH for pepsin is:
2.00
120
4.50 is the optimum pH value for the enzyme:
Sucrase
121
Optimum pH for sucrase is:
4.50
122
Optimum pH for enterokinase enzyme is:
5.50
123
Salivary amylase acts best at pH:
6.8
124
The enzyme with optimum pH=7.60 is;
Catalase
125
The optimium pH of pancreatic lipase is:
9.0
126
The optimum pH for enzyme arginase is:
9.70
127
A little change in pH may lead to:
Ionization of active site of an enzyme
128
Extreme changes in pH cause the bonds in the enzyme to break, resulting in the enzyme:
Denaturation
129
Upon increasing the temperature the shape of enzyme's active site?
Denatures
130
The optimum pH for enzyme arginase is which of the following?
9.7
131
The optimum pH for the function of the enzyme pepsin is?
2
132
If we add more substrate to an already occurring enzymatic reaction and it has no effect on the rate of reaction, the process is called?
Saturation
133
pH of salivary amylase is:
6.8
134
It works in acidic medium
Enterokinase
135
Extreme chagne in pH results in which of the following?
Denaturation of the enzyme
136
What is meant by optimum temperature of an enzyme?
The tempertature at which an enzyme makes the maximum amount of product
137
Rate of reaction is double for rise of every _____.
10C
138
Which of the following strategies of enzymatic inhibition is used by noncompetitive inhibitors?
Bind to an allosteric site to cause a conformational shift in the enzyme
139
If more substrate to an already occuring enzymatic reaction is added more enzyme activity is seen because:
There is probably more substrate present than there is an enzyme
140
The optimum pH for the functioning of pancreatic lipase is?
9
141
A researcher has designed a new type of inhibitor that binds at the active site of an enzyme. What type of inhibition does this molecule display?
Competitive inhibition
142
Which of the following changes could lead to loss of enzymatic function?
Increase in pH of the reaction
143
Which statement correctly describes why enzyme activity increases with increased enzyme concentration?
Collisions between enzyme and substrate molecules because more active sites are available
144
The rate of reaction enzyme directly depends upon which of the following?
Amount of enzyme present at a specific time at an unlimited substrate concentration
145
The enzyme-substrate complex is formed in which part of the enzyme molecule?
Binding site
146
Which step, causes activation of the catalytic site of an enzyme?
Formation of enzyme-substrate site
147
If the concentration of enzyme is kept constant and the amount of substrate is increased a point is reached where an increase in substrates concentration does not affect the reaction rate because of:
All the active sites on the enzyme molecule are occupied
148
What is the optimum temperature for working enzymes in the human body?
37C
149
In an acidic medium, amino acids carry a positive charge and act as:
Base
150
If we increase the pH then, enzyme reactivity is retarded due to:
The tertiary structure of the enzyme is destroyed
151
When we increase the concentration of substrate then an increase in the enzyme activity is due to which of the following?
It is a sufficient concentration of enzyme
152
At low enzyme concentration, optimum pH and temperature, the rate of reaction can be increased by:
Increasing enzyme concentration
153
The number of substrate molecules converted into the product by one molecule of enzyme active site per unit is called
Turn over number
154
The competitive inhibitors have structural similarities with:
Substrate
155
Which of the following type of inhibitor can be neutralized by adding more substrate into the reaction?
Reversible inhibitor
156
If a molecule can bind to another site of the enzyme rather than the true active site, it is referred to as:
Non-Competitive inhibitors
157
What is common in both competitive and non-competitive inhibition?
Reversible inhibition
158
A student of chemical engineering mistakenly engulfed the toxic compound "A" which was a potent inhibitor of certain enzymes. He was immediately brought to the hospital where the doctor injected intravenously substrate "B" to minimize the toxic effect of compound A. His life was saved from serious damage. The treatment method shows that compound A was a ____ inhibitor.
Competitive Reversible
159
Penicillin, an antibiotic inhibits bacterial growth. It is characterized as:
Irreversible inhibitors
160
Which of the following is not an inhibitor of enzymes?
Sucrose
161
Heavy metal ions that act as inhibitors (mercury, silver and copper) break ____ in enzymes.
Disulphide bridges
162
Poisons like cyanide, antibiotics and some drugs are examples of:
Inhibitors
163
The inhibitors that bind tightly and permanently to enzymes and destroy their globular structure stopping their catalytic activity are:
Irreversible inhibitors
164
The type of inhibition in which the inhibitor has no structural similarity to the substrate and combines with the enzyme at other than the active site is called:
➡Non-competitive
➡Reversible inhibition
165
Enzyme succinate dehydrogenase converts succinate into:
Fumarate
166
The effect of a competitive inhibitor on enzyme activity is such that it affects which of the following?
Decreases enzyme activity
167
What is the characteristic of a non-competitive inhibitor?
Adding more substrate does not reduce the effects of inhibition
168
Do reversible inhibitors form weak linkages with which of the following?
Enzyme
169
Inhibitors which block the enzyme by forming weak bonds are called:
Competitive inhibitors
170
Do reversible inhibitors form weak linkages with which of the following?
Enzyme
171
The end product of an enzymatic reaction inhibits the formation of the product in an earlier step. This type of enzymatic regulation is known as:
Feedback Inhibition
172
In incompetitive inhibition, the inhibitor binds with:
Enzyme
173
In mixed inhibition, the allosteric effects:
Shape of enzyme
174
The non-substrate molecules that bond to the allosteric sites are called?
Inhibitors
175
A chemical substance which can react (in place of the substrate) with the enzyme but is not transformed into a product/s and thus blocks the active site temporarily or permanently is called?
Inhibitor
176
Malonic acid is an example of which type of inhibitor.
Competitive Inhibitors
177
In non-competitive inhibition, the quantity which remains the same as the reaction proceeds are?
Km
178
A substrate which binds at the active site of the enzyme but does not result in the formation of the products is called:
Competitive inhibitor
179
An inhibitor is added, disrupting the function of a particular enzyme. The experimenter adds more substrate, and enzyme function increases again. These results indicate the involvement of what type of inhibitor?
Competitive
180
What is meant by enzyme denaturation?
➡Peptide bonds between amino acid residues are broken
➡The enzyme loses its secondary structure
➡The enzyme loses its tertiary structure
✅All of the above
181
The effect of a competitive inhibitor on enzyme activity is such that it affects which of the following?
Decreases enzyme activity
182
The non-substrate molecules that bind to the allosteric sites are called?
Inhibitors
183
Which of the following best describes competitive inhibitors?
Resemble structurally with the substrate
184
____ is a competitive inhibitor of succinic dehydrogenase.
Malonic acid
185
In competitive inhibition, a thing that binds to the enzyme active site is?
Inhibitors
186
Feedback inhibition in most metabolic pathways involves which type of enzymes?
Allosteric enzymes
187
These form weak linkages with enzymes:
Reversible inhibition
188
In uncompetitive inhibition, the inhibitor bonds with:
ES Complex
189
An allosteric enzyme will have:
Many binding sites
190
In mixed inhibition, the inhibitor binds to:
Allosteric site
191
Competitive inhibitors ____ enzyme activity.
Decrease
192
The structure of the enzyme is altered by:
Non-Competitive inhibitor
193
In competitive inhibition, two things attached to the enzyme's active site are:
Substrate
194
The structure of an enzyme is altered by which of the following inhibition?
Irreversible inhibitor
195
Do phosphatases belong to which group of the following?
Hydrolases
196
Cytochrome oxidase is categorized in:
Oxidoreductases
197
Conversion of glucose 6-phosphate into fructose 6-phosphate is done by:
Isomerases
198
A statement that is not correct about enzymes;
➡They increase the rate of reaction❌
➡They contaminate end product✅
➡They lower the activation energy❌
➡They cannot start chemical reactions❌
199
When apoenzyme is separated from its metal compoenent, its activity is:
Lost
200
Synthesis of enzymes takes place by:
Translation
201
This is the core of induce fit model which distinguishes it from lock and key model
Change in enzyme
202
Which of the following is common between Lock and Key model and Induce Fit model?
Enzymes are specific in nature
203
Extreme changes in pH cause denaturation of enzyme by breakign:
Ionic bond
204
After a certain limiting concentraion of substrate, increasing the concentration of enzyme two times, rate of reaction will:
Remain constant
205
Their effect can be neutralized completely or partly by an increase in the concentration of substrate;
Reversible competitive
206
In an enzyme controlled chain reaction, if concentration of initial substrate is increased then it will cause:
Precursor activation
207
The enzyme needed in biological systems for joining two molecuels is called;
Ligases
208
Cofactors are;
➡Prosthetic groups
➡metallic ions
➡Co-enzymes
209
In eukaryotes, enzymes are mostly
Bound to organelles
210
Synthesis of enzymes takes place by;
Translation
211
The catalytic activity of an enzyme is restricted to a small portion of the structure known as:
Active site
212
An enzyme and its substrate react with each other through a definite charge bearing site called;
Active site of enzyme
213
If any factor alters the chemistry and configuration of an enzyme, it will probably be:
➡Temperature
➡pH
➡Inhibitor
214
The rate of reacton depends directly on the amount of enzyme present at a specific time at;
Unlimited substrate concentration
215
Their effect can be neutralized completely or partly by an increase the concentration of substrate;
Reversible competitive
216
In Krebs cycle, malonic acid blocks succinic dehydrogenase thorugh;
Reversible competitive inhibition
217
They occupy the active sites by forming covalent bonds;
Irreversible inhibitors
218
Any agent which reduces/slows down or stops the rate of reacton of enzymes is termed as
Inhibitor
219
In an enzyme controlled chain reaction, if concentraion of initial substrate is increase then it will cause;
Precurosr activation
220
In feedback inhibition, a metabolic pathway is switched off by:
Accumulation of end product
221
Amylase is an example of ;
Hydrolase
222
The enzymes catalyzing re-arrangement of atomic grouping without altering molceular weight or number of atom is;
Isomerases
223
The enzyme needed in biological systems or joining two molecules is called:
Ligases
224
Which of the following is more specific?
➡Lactase✅
➡Pepsin❌
➡Trypsin❌
➡Lipase❌
225
Which of the following is an example of a coenzyme?
FAD+ in Krebs cycle during succinate conversion to fumarate
226
The optimum pH for working of pancreatic lipase is:
9.00
227
Phosphorylation of glucose is done by:
Kinase
228
An enzyme which catalyzes different substrates into single product:
Hexokinase
229
ATP binds to ____ of phosphofructokinase:
Allosteric site
230
The temperature where an inactive enzyme becomes active again is called:
Minimum Temperature
231
Changing the pH from optimum results in:
Decrease in rate of reaction
232
Which of the followings is not an inhibitor of enzymes?
Maltose
233
Which enzyme can digest the following molecule?
➡Amylase❌
➡Pepsin❌
➡Lipase✅
➡Lactase❌
234
A protein that is not an enzyme:
➡Isomerase❌
➡Rennin❌
➡Prolactin✅
➡Maltase❌
235
The active site of an enzyme:
Determines by its structure the specificity fo the enzyme
236
Which of the following is the features of the enzymes:
➡Non-Crystalline❌
➡Spindle Shape❌
➡Soluble in aqueous medium✅
➡Fibrous Shape❌
237
The essential chemical components of many coenzymes are:
Vitamins
238
Select the option which is not correct with respect to enzyme action:
➡The addition of succinate does not reverse the effect produced by malonate✅
➡Malonate is a competitive inhibitor o succinate dehydrogenase❌
239
The specificity of enzyme was first proposed by:
E. Fischer
240
The temperature, where an inactive enzyme becomes active again, is called:
Minimum Temperature
241
All enzymes follow the induced fit model except:
➡Carbonic anhydrase❌
➡Allosteric Enzymes❌
➡Hexokinase❌
➡Urease✅
242
Cyanides are potent poisons for the living organisms because they can kill by inhibiting ____, essential for cellular respiration.
Cytochrome Oxidase
243
Penicillin control bacterial infection by:
Reversible Non-Competitive
244
Which one of the following is called biological catalysts?
Enzymes
245
The active site of enzymes consists of:
Only a few amino acids
246
_______ maintains the globular structure of the enzyme
The bulk of amino acids
247
Often it contributes directly to the chemical reactions which bring about catalysis:
Co-Factor
248
If the non-protein part of the enzyme is covalently bonded to the protein part, it is called
Co-Enzyme
249
An activated enzyme consisting of polypeptide chain and a cofactor is known as:
Holoenzyme
250
Enzymes are sensitive to even a minor change in:
➡pH
➡Temperature
➡Substrate COncentration
251
________ is a powerful protein digesting enzyme and is capable of destroying a cell’s internal structure and thus produced in inactive ________ form by the cell
Pepsin, Pepsinogen
252
After the formation of products, it is released unaltered and thus can be used again:
Enzyme
253
Enzymes involved in some metabolic pathways are normally present together:
In precise order
254
The charge and shape of the active site of the enzyme is formed by _______ in the polypeptide chain of the active site of the enzyme.
Some amino acids
255
The reaction between _______ activates the catalytic site of the enzyme
Substrate and Binding site of the enzyme
256
According to this model enzyme is a rigid structure:
Lock and Key Model
257
According to ________ the active site of enzyme is not a rigid structure
Induced Fit Model
258
The functional specificity of every enzyme is the consequence of its:
Specific chemistry and Cofiguration
259
The rate of reaction depends directly on the amount of enzyme provided the substrate concentration is
Unlimited
260
By increasing the enzyme molecules ________ will convert the substrate molecules into products, in the given period of time.
More active sites
261
If the enzyme conc. is kept constant, by increasing the substrate concentration the rate of enzyme action is
Increased or specific time
262
The rate of enzyme-controlled reactions may increase with the increase in:
Temperature up to optimum level
263
Chemical reactions are accelerated at high temperature because
Heat provides the activation energy
264
When reactants move more quickly and chances of their collision with each other are increased as a result the rate of enzyme-controlled reactions will?
Increase Initially
265
Inhibitors can be divided into:
Two basic types
266
They alter the structure of the enzyme in such a way that even if genuine substrate binds the active site, catalysis fails to take place temporarily:
Non-Competitive Inhibitors
267
Pick up the product:
➡Succinic Acid❌
➡Malonic Acid❌
➡Fumaric Acid✅
➡Dehydrogense❌
268
Succinic acid dehydrogenase + malonic acid ➡
No reaction possible, Enzyme is blocked
269
Which one of the following is reused?
Enzyme and Co-enzyme
270
Some enzymes are potentially damaging if they are manufactured in their active form e.g.
Pepsin
271
Which one of the following products will
control this pathway through feedback
activation?
A➡B➡C➡D➡E
E
272
Which one of the following products will control this pathway through feedback action
A➡B➡C➡D
E
273
A➡B➡C➡D➡E
Accumulation of "E" will control the above pathway through:
Feedback Inhibition
274
A➡B➡C➡D➡E
A deficiency of “E” will control the above
pathway through:
Feedback activation
275
Induce fit model was proposed by
Koshland
276
Salivary amylase works best at pH:
6.80
277
Optimum pH for the action of pancreatic lipase is:
9.00
278
Malonic acid is competitive inhibitor of:
Succinic Dehydrogenase
279
It causes denaturation of globular structure of enzyme:
Extreme pH change
280
Any molecule that increases the rate of a chemical reaction without being used up during that reaction is called:
Catalyst
281
Enzymes are not synthesized in:
Viruses
282
Enzymes enhance the rate of reaction by:
Lowering the activaton energy of the reaction
283
Which enzyme hydrolyses internal phosphodiester bonds in a polynucleotide chain?
Endonuclease
284
Which one of the following statements regarding enzyme inhibition is correct?
Competitive inhibition is seen when substrate and inhibitor compete
285
A competitive inhibitor of succinic dehydrogenase is:
Malonic acid
286
Enzymes often have additional parts in their structures that are made up of molecules other than proteins. When this additional chemical part is an organic molecule, it is called:
Co-Enzyme
287
The lipid synthesizing enzymes are present in:
Smooth ER
288
The term apoenzyme is applicable to:
Protein part of conjugate enzyme
289
Enzymes:
290
Enzymes generally have:
Different pH but same optimum temperature
291
Koshland's model of enzyme action is known as:
Induced Fit model
292
Enzymes having slightly different molecular structure but performing identical activity are:
Isoenzymes
293
Which factor is responsible for the inhibition enzymatic process during feedback
End Product
294
One which is not an inhibitor:
Metabolites
295
Some of the enzymes, which are associated with converting fats into carbohydrates, are present in:
Glyoxysomes
296
Any molecule which acts directly on an enzyme to lower its catalytic rate is called:
Inhibitor
297
Which of the following statements is true regarding enzyme inhibition?
➡It may be reversible or irreversible
➡Reversible can be competitive or noncompetitive
298
The effect of a reversible competitive inhibitor can be nullified by:
Increasing the substrate concentration
299
The ____ acts as a "bridge" between the enzyme and its substrate.
Co-Factor
300
One which is inorganic in nature:
Activator
301
The following is a substrate-specific enzyme:
➡Pepsin❌
➡Protease❌
➡Lipase❌
➡Sucrase✅
302
Regarding the nature of enzymes, which one is correct?
They are specific both in their nature and action
303
Regarding enzyme molecules:
Greater in size than the substrate
304
The temperature at which enzymes can work at their maximum rate is called ____ temperature.
Optimum
305
The optimum pH for enterokinase is:
5.50
306
Which of the following does not work on an acidic medium:
Arginase
307
An enzyme and substrate react through a special feature or site present in an enzyme known as:
Active Site
308
Enzymes increase the rate of reaction by:
Decreasing activation energy
309
The non-protein part of enzyme which is covalently bonded is called:
Prosthetic Group
310
Most vitamins are
Co-Enzymes
311
Which of the following is a co-factor?
➡Calcium Ions
➡Copper Ions
➡Manganese ions
312
Co-Enzymes combine with:
Apoenzyme
313
The non-competitive inhibitor is one that:
Binds away from the active site of an enzyme
314
The shape of enzyme molecule is:
Globular
315
The protein cytochrome c functions only when it contains an atom of iron. Which term describes the atom of iron?
Part of a prosthetic group
