microbiology ch 5 Flashcards
1
Q
What breaks down complex molecules, provides energy and building blocks for anabolism, and is exergonic and hydrolytic?
A
Catabolism
2
Q
What reactions produce more energy than they consume?
A
Exergonic
3
Q
These reactions use water and break chemical bonds
A
Hydrolytic
4
Q
What do hyrdolytic reactions do?
A
Break chemical bonds using water
5
Q
What type of reactions use energy to build complex molecules, are endergonic and use dehydration synthesis?
A
Anabolism
6
Q
These reactions consume more energy than they produce
A
Endergonic
7
Q
These reactions release water
A
Dehydration synthesis
8
Q
What is a metabolic pathway?
A
Sequence of enzymatically catalyzed chemical reactions in a cell
9
Q
What determines metabolic pathways?
A
Enzymes
10
Q
What are enzymes encoded by?
A
Genes
11
Q
These are sequences of enzymatically catalyzed chemical reactions in a cell
A
Metabolic pathways
12
Q
Enzymes determine these
A
Metabolic pathways
13
Q
Genes encode these
A
Enzymes
14
Q
What does collision theory state?
A
That chemical reactions occur when atoms, ions, and molecules collide
15
Q
What is the basis of collision theory?
A
That all atoms, ions, and molecules are continuously moving and colliding with one another
16
Q
What can the energy transferred by colliding particles do?
A
Break chemical bonds or form new bonds
17
Q
This states that chemical reactions occur when atoms, ions, and molecules collide
A
Collision theory
18
Q
This explains how chemical reactions occur and how certain factors affect the rates of those reactions
A
Collision theory
19
Q
How can chemical bonds be broken or formed?
A
By the energy transferred to them during collision breaking their electron structures
20
Q
What is activation energy?
A
The collision energy required for a chemical reaction to occur
21
Q
What is reaction rate?
A
The frequency of collisions containing enough energy to bring about a reaction
22
Q
What four factors can increase reaction rate?
A
Enzymes, increasing temperature, increasing pressure, increasing concentration
23
Q
This is the collision energy needed for chemical reactions to occur
A
Activation energy
24
Q
This is the frequency of collisions with enough energy to cause reactions
A
Reaction rate
25
Enzymes, or increases in temperature, pressure, or concentration can cause this
Reaction rate increase
26
What are enzymes?
Biological catalysts
27
What can catalysts do?
Speed up chemical reactions without being altered
28
What do enzymes act on?
A specific substrate
29
How do enzymes increase the rate of reaction?
By lowering activation energy
30
These are biological catalysts
Enzymes
31
These can speed up chemical reactions without being changed themselves
Catalysts
32
What is an enzyme-substrate complex?
Formation of enzyme's active site and substrate
33
What happens to the substrate on an enzyme's active site?
It is transformed, rearranged into products, and released from enzyme
34
What happens to the enzyme after the substrate is released?
The enzyme is unchanged and can react with other substrates
35
This is formed by joining a substrate to an enzyme's active bonding site
Enzyme-substrate complex
36
What is turnover number?
The number of substrate molecules an enzyme converts to a product per second
37
How high can enzyme turnover number be?
500,000
38
What is the general range of enzyme turnover?
1 to 10,000
39
This is the number of substrate molecules an enzyme converts to a product per second
Turnover number
40
What do enzyme names typically end with?
-ase
41
What are enzyme names based on?
The reaction they catalyze
42
What reactions is oxidoreductase involved with?
Oxidation-reduction reactions
43
What reactions is transferase involved with?
Transfer of functional groups such as amino, acetyl, and phosphate groups
44
What reactions is hydrolase involved with?
Hydrolysis
45
What reactions is lyase involved with?
Removal of atoms without hydrolysis
46
What reactions is isomerase involved with?
Rearrangement of atoms within a molecule
47
What reactions is ligase involved with?
Joining of molecules using ATP
48
This enzyme is involved with oxidation-reduction reactions
Oxidoreductase
49
This enzyme is involved in functional group transfer
Transferase
50
This enzyme is involved with hydrolysis
Hydrolase
51
This enzyme is involved with the removal of atoms without hydrolysis
Lyase
52
This enzyme is involved with the rearrangement of atoms within a molecule
Isomerase
53
This enzyme is involved in the joining of molecules using ATP
Ligase
54
What are coenzymes/cofactors?
Enzyme 'helpers'/electron carriers
55
What four factors influence enzyme activity?
Temperature, pH, substrate concentration and inhibitors
56
How does high temperature influence enzyme activity?
High temperature can denature proteins
57
What does it mean to denature a protein?
Loss of its characteristic three-dimensional structure (tertiary configuration)
58
How can extreme pH influence enzyme activity?
By denaturing proteins
59
Do enzymes have an optimum pH?
Yes
60
Do enzymes catalyze faster with a higher substrate concentration?
Yes
61
What is saturation?
When concentration of substrate is high enough for enzyme to catalyze at maximum rate
62
When substrate concentration is high and enzyme catalyzes at maximum rate, this is reached
Saturation
63
What do competitive inhibitors do?
Fill active site of an enzyme and compete with substrate
64
This fill the active site of an enzyme and compete with the substrate
Competitive inhibitors
65
What do noncompetitive inhibitors do?
Interact with another part of enzyme rather than active site
66
What is allosteric inhibition?
Interaction of noncompetitive inhibitors with enzyme
67
What is an allosteric site?
A site other than the active site
68
How do noncompetitive inhibitors render enzymes nonfunctional?
By altering the shape of the active site
69
These interact with an allosteric site to render enzyme nonfunctional
Noncompetitive inhibitors
70
This is a site on an enzyme that is not its active site
Allosteric site
71
This is the interaction of noncompetitive inhibitors with an enzyme
Allosteric inhibition
72
What is feedback inhibition?
End-product of reaction allosterically inhibits enzymes from earlier in pathway
73
This happens when a reaction end-product allosterically inhibits an enzyme at an earlier point in pathway
Feedback inhibition
74
What are ribozymes?
RNA that function as catalysts by binding to substrates and acting upon them
75
What are ribozymes used for in cells?
To cut and splice RNA; also involved in protein synthesis in ribosomes
76
Are ribozymes used up in the reaction?
No
77
These are RNA that function as catalysts
Ribozymes
78
These are used in cells to cut/splice RNA and to synthesize proteins and ribosomes
Ribozymes
79
What is the removal of electrons called?
Oxidation
80
What is the gain of electrons called?
Reduction
81
What is the pairing of an oxidation reaction and a reduction reaction called?
Redox reaction
82
What is oxidation?
Removal of electrons
83
What is reduction?
Gain of electrons
84
What is a redox reaction?
An oxidation reaction paired with a reduction reaction
85
What are removed simultaneously in biological systems?
Electrons and protons
86
What is an electron and proton the equivalent of?
One hydrogen atom
87
Biological oxidations are often this type of reaction
Dehydrogenations
88
What is dehydrogenation?
Loss of hydrogen atoms
89
How are electrons and protons removed in biological systems?
Simultaneously
90
What is the equivalent of one hydrogen atom?
One electron and proton
91
This is the loss of hydrogen atoms
Dehydrogenation
92
How is ATP generated?
By the phosphorylation of ADP with the input of energy
93
What is generated by the phosphorylation of ADP with the input of energy?
ATP
94
What is generated when high-energy PO4- is added to ADP from a phosphorylated compound?
ATP
95
What has to be added to ADP from a phosphorylated compound to generate ATP?
High-energy PO4-
96
This transfers electrons from one electron carrier to another
Electron transport chain
97
The electron transport chain transfers electrons along a membrane, releasing energy to generate this
ATP
98
What is the process wherein ATP is generated from ADP using energy derived from the electron transport chain?
Chemiosmosis
99
What is the electron transport chain?
Electrons transferred from one electron carrier to another along a membrane that releases energy to generate ATP
100
What is chemiosmosis?
The process wherein ATP is generated from ADP using the energy derived from the electron transport chain
101
In what type of cells does photophosphorylation occur?
In photosynthetic cells with light-trapping pigments
102
What is the process of photophosphorylation?
Light energy is converted to chemical energy (ATP) during the transfer of electrons (oxidation) from chlorophyll as they pass through a system of carrier molecules
103
In photosynthetic cells with light-trapping pigments such as chlorophyll, this occurs
Photophosphorylation
104
In this process, light energy is converted to chemical energy during the transfer of electrons from chlorophyll as they pass through a system of carrier molecules
Photophosphorylation
105
What are series of enzymatically catalyzed chemical reactions that extract energy from organic compounds and store it in chemical form?
Metabolic pathways
106
How do metabolic pathways store extracted energy?
As ATP
107
What is carbohydrate catabolism?
The breakdown of carbohydrate molecules to produce energy
108
What is the most common carbohydrate energy source used by cells?
Glucose
109
In addition to glucose, what can microbes use as energy sources?
Lipids and proteins
110
This is the breakdown of carbohydrate molecules to produce energy
Carbohydrate catabolism
111
What is the oxidation of glucose to pyruvic acid to produce ATP and NADH?
Glycolysis
112
What does "glycolysis" mean?
"Splitting sugar"
113
What is glycolysis?
The oxidation of glucose to pyruvic acid to produce ATP and NADH
114
What does glycolysis produce?
ATP and NADH
115
What happens in the preparatory stage of glycolysis?
2 ATP are used, glucose is split to form two molecules, and DHAP is converted to GP
116
In this stage of glycolysis, 2 ATP are used to split glucose to form one GP and one DHAP, and DHAP is readily converted to GP
Preparatory stage
117
What two molecules is glucose used to form during the preparatory stage of glycolysis?
Glyceraldehyde 3-phosphate (GP) and dihydroxyacetone phosphate (DHAP)
118
How many ATP are used during the preparatory stage of glycolysis?
2
119
Which molecule is converted into which at the end of the preparatory stage of glycolysis?
Dihydroxyacetone phosphate (DHAP) is converted into glyceraldehyde 3-phosphate (GP)
120
What happens during the energy-conserving stage of glycolysis?
The two GP molecules are oxidized to 2 pyruvic acid molecules, 4 ATP are produced, and 2 NADH are produced
121
How many glyceraldehyde 3-phosphate (GP) molecules are oxidized into pyruvic acid during the energy-conserving stage of glycolysis?
2
122
How many pyruvic acid molecules are formed from glyceraldehyde 3-phosphate (GP) during the energy-conserving stage of glycolysis?
2
123
How many ATP are produced during the energy-conserving stage of glycolysis?
4
124
How many NADH are produced during the energy-conserving stage of glycolysis?
2
125
During this stage of glycolysis, two glyceraldehyde 3-phosphate molecules are oxidized to two pyruvic acid molecules, 4 ATP are produced, and 2 NADH are produced
Energy-conserving stage
126
What is the overall net gain of ATP for each molecule of glucose oxidized during glycolysis?
2
127
What are the products of this equation: Glucose + 2ATP + 2ADP 2 PO4- + 2NAD+ --->
2 pyruvic acid + 4ATP + 2NADH + 2H
128
What types of sugar does the pentose phosphate pathway break down?
Pentose and/or glucose
129
What does the pentose phosphate pathway produce?
NADPH
130
Does the pentose pathway operate simultaneously with glycolysis?
Yes
131
What 3 intermediates can the pentose phosphate pathway provide?
Nucleic acids, glucose, certain amino acids
132
How many molecules of ATP does the pentose phosphate pathway yield for each molecule of glucose oxidized?
1
133
Which species of bacteria utilizes the pentose phosphate pathway?
E. coli
134
This pathway breaks down pentose sugars and/or glucose, produces NADPH, can provide intermediates for synthesis reactions, and yields one molecule of ATP per molecule of glucose oxidized
Pentose phosphate pathway
135
This pathway operates simultaneously with glycolysis
Pentose phosphate pathway
136
Can the pentose phosphate pathway produce intermediates for synthesis reactions?
Yes
137
Does the pentose phosphate pathway yield 2 ATP molecules for every 1 glucose molecule oxidized?
No
138
This pathway is utilized by E. coli
Pentose phosphate pathway
139
What three molecules does the Entner Doudoroff pathway produce from 1 glucose molecule?
1 NADPH, 1 NADH, and 1 ATP
140
Does the Entner-Doudoroff pathway operate alongside glycolysis?
No
141
What three groups of bacteria use the Entner Doudoroff pathway?
Pseudomonas, Rhizobium, and Agrobacterium
142
From 1 glucose molecule, this pathway produces one molecule each of NADPH, NADH, and ATP
Entner-Doudoroff pathway
143
This pathway operates independently of glycolysis and the pentose phosphate pathway
Entner-Doudoroff pathway
144
This pathway occurs in Pseudomonas, Rhizobium, and Agrobacterium
Entner-Doudoroff pathway
145
What does aerobic respiration use as a final electron acceptor?
Oxygen
146
What does anaerobic respiration use as a final electron acceptor?
Molecule other than oxygen
147
What generates ATP in cellular respiration?
Oxidative phosphorylation
148
In this, oxidation of molecules liberates electrons to operate an electron transport chain
Cellular respiration
149
What are two requirements for the final electron acceptor in cellular respiration?
Comes from outside the cell and is inorganic
150
This type of cellular respiration uses oxygen as the final electron acceptor
Aerobic respiration
151
This type of cellular respiration uses a molecule other than oxygen as the final electron acceptor
Anaerobic respiration
152
This generates ATP in cellular respiration
Oxidative phosphorylation
153
What is oxidized during the Krebs cycle?
Pyruvic acid
154
What does the pyruvic acid used in the Krebs cycle come from?
Glycolysis
155
What is lost from pyruvic acid during oxidation in the Krebs cycle?
CO2
156
What is the loss of CO2 called?
Decarboxylation
157
After decarboxylation in the Krebs cycle, what does the resulting two-carbon compound form?
Acetyl CoA and NADH
158
What enzyme is used to form acetyl CoA and NADH?
Coenzyme A
159
What does the oxidation of acetyl CoA produce?
NADH, ATP, and waste CO2
160
This process transforms pyruvic acid from glycolysis into NADH, ATP, and CO2
Krebs cycle
161
Pyruvic acid is oxidized and decarboxylated during this process
Krebs cycle
162
Coenzyme A attaches with a two-carbon compound during the Krebs cycle to form these two molecules
Acetyl CoA and NADH
163
NADH, ATP, and CO2 are all produced from this process during the Krebs cycle
Oxidation of acetyl CoA
164
Where does the electron transport chain occur in prokaryotes?
In plasma membrane
165
Where does the electron transport chain occur in eukaryotes?
Inner mitochondrial membrane
166
What are three types of carrier molecules in the electron transport chain?
Flavoproteins, cytochromes, and ubiquinones
167
What happens to carrier molecules as electrons are passed down the electron transport chain?
They are oxidized and reduced
168
What is done with energy released from electron transport chain?
It is used to produce ATP
169
In prokaryotes, the electron transport chain occurs here
Plasma membrane
170
In eukaryotes, the electron transport chain occurs here
Inner mitochondrial membrane
171
Flavoproteins, cytochromes, and ubiquinones are examples of these
Carrier molecules
172
These are oxidized and reduced as electrons are passed down the electron transport chain
Carrier molecules
173
What happens with protons as electrons from NADH are passed down the electron transport chain?
They are pumped across membrane
174
What does the proton motive force come from?
Proton gradient
175
What do protons go through when they diffuse across the membrane?
ATP synthase
176
What is the energy from protons diffusing through ATP synthase used for?
Synthesizing ATP
177
This is the process of establishing a proton gradient to then diffuse protons through ATP synthase to release the energy needed to synthesize ATP
Chemiosmosis
178
How many ATP molecules are made from aerobic respiration?
38
179
How many ADP molecules are used during aerobic respiration?
38
180
How many molecules of ATP are made from oxidizing one NADH in the electron transport chain?
3
181
How many molecules of ATP can one FADH2 make?
2
182
How many NADH molecules are produced throughout carbohydrate catabolism?
12
183
How many FADH2 molecules are produced throughout carbohydrate catabolism?
2
184
How many ATP does substrate-level phosphorylation generate throughout carbohydrate catabolism?
4
185
Does anaerobic respiration yield less energy that aerobic respiration?
Yes
186
What is fermentation?
Process that releases energy from oxidation of organic molecules, does not require oxygen, does not use the Krebs cycle of ETC, and uses an organic molecule as final electron acceptor
187
Can fermentation produce as much ATP as cellular respiration?
No
188
How many molecules of ATP can fermentation produce?
1 or 2
189
This process releases energy from oxidation of organic molecules, does not require oxygen, does not use the Krebs cycle or electron transport chain, and uses an organic molecule as a final electron acceptor
Fermentation
190
In fermentation, pyruvic acid is converted into what?
Organic product
191
What is used as a final electron acceptor in fermentation?
Organic molecule
192
Does fermentation require oxygen?
No
193
Does fermentation release energy from oxidation of organic molecules?
Yes
194
Does fermentation use the Krebs cycle or the electron transport chain?
No
195
Does fermentation produce 1 or 2 ATP?
Yes
196
What does lactic acid fermentation produce?
Lactic acid
197
What does homolactic fermentation produce?
Lactic acid only
198
What does heterolactic fermentation produce?
Lactic acid and other compounds
199
What happens to glucose in fermentation?
It is oxidized to pyruvic acid, which is reduced by NADH
200
This process produces lactic acid
Lactic acid fermentation
201
This process produces lactic acid only
Homolactic fermentation
202
This process produces lactic acid and other compounds, doing both alcohol fermentation and lactic acid fermentation
Heterolactic fermentation
203
This is oxidized to pyruvic acid, which is then reduced by NADH in the fermentation process
Glucose
204
What does alcohol fermentation produce?
Ethanol + CO2
205
In this process, glucose is oxidized to pyruvic acid, pyruvic acid is converted to acetaldehyde and CO2, and NADH reduces acetaldehyde to ethanol
Alcohol fermentation
206
This process produces ethanol and carbon dioxide
Alcohol fermentation
207
What are proteins degraded into by extracellular proteases and peptidases?
Amino acids
208
Can amino acids cross plasma membranes?
Yes
209
What three things are done to amino acids before entering Krebs cycle?
Deamination, decarboxylation, and desulfurization
210
What is deamination?
Removal of amino group to converted to ammonium ion
211
What is decarboxylation?
Removal of carboxylic acid
212
What is desulferization?
Removal of thiol group (-SH)
213
These degrade proteins into amino acids
Extracellular proteases and peptidases
214
These cross plasma membranes to be deaminated, decarboxylated, and desulfurized
Amino acids
215
This is the removal of an amino group to convert into an ammonium ion
Deamination
216
This is the removal of carboxylic acid
Decarboxylation
217
This is the removal of a thiol group
Desulferization
218
How do biochemical tests identify bacteria?
By detecting enzymes
219
Enzymes involved in what are detected in biochemical tests?
Decarboxylation and dehydrogenation
220
These identify bacteria by detecting enzymes involved in decarboxylation and dehydrogenation
Biochemical tests
221
What does an oxidase test identify?
Bacteria that have cytochrome c oxidase
222
What does a catalase test identify?
Bacteria that have catalase
223
What does catalase do?
Neutralizes the bacterial effects of hydrogen peroxide
224
This test identifies bacteria that have cytochrome c oxidase
Oxidase test
225
This test identifies bacteria that have catalase
Catalase test
226
This enzyme neutralizes the bacterial effects of hydrogen peroxide
Catalase
227
What does a fermentation test identify?
Bacteria that catabolize carbohydrate or protein
228
What happens during a positive fermentation test?
The pH indicator changes color
229
Why does the pH indicator change color during a positive fermentation test?
Bacteria that catabolize carbohydrates or protein produce acid
230
This test can also be used with a Durham tube to detect gas production during fermentation
Fermentation test
231
This test identifies bacteria that catabolize carbohydrates or protein by causing a pH indicator to change color
Fermentation test
232
This can be used with a fermentation test to detect gas production
Durham tube
233
What is carbon fixation?
The synthesis of sugar by using carbon atoms from CO2 gas
234
This is the synthesis of sugar by using carbon atoms from CO2 gas
Carbon fixation
235
What organisms are oxygenic photosynthesizers?
Plants, algae, cyanobacteria
236
What organisms are anoxygenic photosynthesizers?
Purple sulfur/green sulfur bacteria
237
What does anoxygenic photosynthesis use in place of water?
H2S
238
What does anoxygenic photosynthesis produce instead of oxygen?
12 Sulfur molecules
239
What happens in light-dependent reactions?
Conversion of light energy into chemical energy
240
What kind of chemical energy to light-dependent reactions produce?
ATP and NADPH
241
What happens in light-independent reactions?
ATP and NADPH are used to reduce CO2 to sugar via Calvin-Benson cycle
242
What is a photosystem made of?
Chlorophyll and other proteins
243
What are used to reduce CO2 to sugar via the Calvin-Benson cycle?
ATP and NADPH
244
What is cyclic photophosphorylation?
Return of electrons released from chlorophyll in photosystem 1 back into chlorophyll
245
During this process, the electrons released from chlorophyll in photosystem 1 eventually return to chlorophyll
Cyclic photophosphorylation
246
During this process, both photosystems are required and electrons do not return to chlorophyll, but become incorporated into NADH
Non-cyclic photophosphorylation
247
What type of organisms use non-cyclic photophosphorylation?
Oxygenic organisms
248
Where do electrons from chlorophyll end up in cyclic photophosphorylation?
Chlorophyll
249
Where do electrons from chlorophyll end up in non-cyclic photophosphorylation?
NADH
250
What do phototrophs use to drive ATP production?
Light
251
What do photoautotrophs do?
Use energy initially obtained from light to fix CO2 to sugar during Calvin-Benson cycle
252
What do photoheterotrophs use as a source of carbon?
Organic compounds
253
These use light energy to drive ATP production
Phototrophs
254
These use energy obtained initially from light in the Calvin-Benson cycle to fix CO2 to sugar
Photoautotrophs
255
These use organic compounds as a source of carbon
Photoheterotrophs
256
Are photoheterotrophs anoxygenic?
Yes
257
What do chemoautotrophs get energy from?
Inorganic chemicals
258
What do chemoautotrophs use as a carbon source?
CO2
259
What do chemoautotrophs use energy to do in the Calvin-Benson cycle?
Fix CO2
260
These obtain energy from inorganic chemicals
Chemoautotrophs
261
These use CO2 as carbon source
Chemoautotrophs
262
Energy is used to fix CO2 during this process
Calvin-Benson cycle
263
What to chemoheterotrophs obtain from organic chemicals?
Carbon and energy
264
Are chemoheterotrophs medically and economically important?
Yes
265
These obtain energy and carbon from organic chemicals
Chemoheterotrophs
266
What are amphibolic pathways?
Metabolic pathways that function in both anabolism and catabolism
267
What role do amphibolic pathways play?
Amphibolic pathways bridge the reactions that lead to the breakdown and synthesis of carbohydrates, lipids, proteins, and nucleotides
268
These are metabolic pathways that function in both anabolism and catabolism
Amphibolic pathways
269
Do many pathways function simultaneously with common intermediates?
Yes
270
These pathways bridge reactions leading to breakdown/synthesis of carbohydrates, lipids, proteins, and nucleotides
Amphibolic pathways
