Quiz 3 Flashcards
From the standpoint of the microorganism, in glycolysis the crucial product is
From the standpoint of the microorganism, in glycolysis the crucial product is
- ethanol or lactate; ATP is a waste product.
- CO2; ATP is a waste product.
- ATP; the fermentation products are waste products.
- not relevant because glycolysis is not a major pathway.
ATP; the fermentation products are waste products.
Chemolithotrophs that obtain electrons from donors such as sulfide use the same electron transport chains to obtain energy as chemoorganotrophs.
T/F
true
Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes). Among the halophiles, mannitol fermenters release acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol nonfermenter and a nonhalophilic mannitol nonfermenter. Here the medium acts as a __________ medium.
- Selective and differential
- Selective
- Differential
- Enrichment
Selective & differential
pathogens can be readily grown in laboratory culture.
Many pathogens can be readily grown in laboratory culture.
True
False
T
The net gain of ATP per molecule of glucose fermented is
The net gain of ATP per molecule of glucose fermented is
4.
2.
1.
8.
Two
Fermentation produces 4 ATP molecules per molecule of glucose, compared to 38 by aerobic respiration. Since 2 ATP molecules are used in glycolysis, the net yield for fermentation is 2 ATP.
Which of the following characteristics is not true of beta haemolysis?
Which of the following characteristics is not true of beta haemolysis?
Complete haemolysis
Colourless zone of clearing
Sharply defined zone of clearing
Narrow zone of clearing (<2mm)
narrow zone of clearing (<2mm)
Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes); nonhalophiles will not grow. Among the halophiles, mannitol fermenters will produce acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol fermenter and a halophilic mannitol nonfermenter. In this case, the medium is acting as (a) __________ medium(s).
Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes); nonhalophiles will not grow. Among the halophiles, mannitol fermenters will produce acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol fermenter and a halophilic mannitol nonfermenter. In this case, the medium is acting as (a) __________ medium(s).
Selective and differential
Selective
Enrichment
Differential
-
Fermentation has a relatively low ATP yield compared to aerobic respiration because
Fermentation has a relatively low ATP yield compared to aerobic respiration because
less ATP is consumed during the first stage of aerobic catabolism.
oxidative phosphorylation yields a lot of ATP.
more reducing equivalents are used for anaerobic catabolism.
substrate-level phosphorylation yields a lot of ATP.
oxidative phosphorylation yields a lot of ATP.
The rising of bread dough is the result of
The rising of bread dough is the result of
oxidative phosphorylation.
biotin production.
oxygen being released.
carbon dioxide produced by fermentation.
carbon dioxide produced by fermentation.
Some anaerobic bacteria not only use organic compounds as a carbon source but can also use them for energy as well.
Some anaerobic bacteria not only use organic compounds as a carbon source but can also use them for energy as well.
True
False
T
In aerobic respiration, the final electron acceptor is
In aerobic respiration, the final electron acceptor is
oxygen.
water.
ATP.
hydrogen.
O
For a carbon source, chemoorganotrophs generally use compounds such as
For a carbon source, chemoorganotrophs generally use compounds such as
acetate, succinate, and glucose.
bicarbonate and carbon dioxide.
acetate, bicarbonate, and nitrate.
nitrate and nitrite.
acetate, succinate, and glucose.
The net result of electron transport is the generation of a pH gradient and an electrochemical potential across the membrane.
The net result of electron transport is the generation of a pH gradient and an electrochemical potential across the membrane.
True
False
T
Fermentation of organic compounds, such as acetate, produces NADH and ATP.
Fermentation of organic compounds, such as acetate, produces NADH and ATP.
True
False
F
The OF test differentiates bacteria on the basis of fermentative or oxidative metabolism of glucose.
The OF test differentiates bacteria on the basis of fermentative or oxidative metabolism of glucose.
True
False
T
Blood agar is often used to differentiate between:
Blood agar is often used to differentiate between:
Types of hemolysis the bacteria may produce.
Salt sensitive and non-salt sensitive microbes.
Bacteria that absorb oxygen and those that do not.
All of the above.
Types of hemolysis the bacteria may produce.
In cases of suspected foodborne or waterborne infections, fecal samples should be inoculated into a variety of selective media.
In cases of suspected foodborne or waterborne infections, fecal samples should be inoculated into a variety of selective media.
True
False
T
What metabolism would be favored when there is a lack of electron acceptors?
What metabolism would be favored when there is a lack of electron acceptors?
acetogenesis
anaerobic fermentation
anoxygenic photosynthesis
anoxic ammonia oxidation
anaerobic fermentation
You inoculated and then incubated an oxidation/fermentation (OF) test over the past 5 days. You return to find that the top third of the media has transformed from green to yellow. From this you derive that the inoculated bacteria _________ .
You inoculated and then incubated an oxidation/fermentation (OF) test over the past 5 days. You return to find that the top third of the media has transformed from green to yellow. From this you derive that the inoculated bacteria _________ .
Is a mannitol fermenter
Utilises a fermentative metabolism
Contains the enzyme Oxidase
Utilises an oxidative metabolism
Utilises an oxidative metabolism
Which of the following would be used by a chemoorganotroph for energy?
Which of the following would be used by a chemoorganotroph for energy?
CO2
H2
C2H3O2-
H+
C2H3O2-
