Ch.3 Microbial Metabolism
The prokaryotic transport system that involves a substrate-binding protein, a
membrane-integrated transporter, and an ATP-hydrolyzing protein is A) the ABC transport
system. B) group translocation. C) symport. D) simple transport. - ANS A the ABC transport
system
The sum of all biosynthetic reactions in a cell is known as A) metabolism. B) anabolism. C)
catabolism. D) synthatabolism. - ANS B anabolism
Based on the functional roles of phosphate in various microbial metabolisms, which of the
following compounds most likely contain phosphate? A) organic compounds B) inorganic
compounds C) both organic and inorganic compounds D) neither organic nor inorganic
compounds - ANS C both organic and inorganic compounds
Which of the following would be used by a chemoorganotroph for energy? A) C2H3O2- B) H2
C) CO2 D) H+ - ANS A C2H3O2-
Which of the following statements is FALSE? A) Most bacteria are capable of using ammonia as
their sole nitrogen source. B) Some bacteria are able to use nitrates or nitrogen gas as their
nitrogen source. C) Most available nitrogen is in organic forms. D) Nitrogen is a major
component of proteins and nucleic acids. - ANS C most available nitrogen is in organic forms
All microorganisms require A) carbon, iron, and sodium. B) phosphorus, aluminum, and sodium.
C) calcium, potassium, and magnesium. D) phosphorus, selenium, and sulfur. - ANS D
phosphorus, selenium, and sulfur
Which element functions BOTH as an enzyme cofactor and as a stabilizer of ribosomes and
nucleic acids? A) iron B) hydrogen C) zinc D) magnesium - ANS D magnesium
Based on your understanding of metabolism, generalize when an enzymeʹs rate of activity can
be changed. A) before enzyme production B) during enzyme production C) after enzyme
production D) at any point—before, during, or after enzyme production - ANS C after enzyme
production
The change in Gibbs free energy for a particular reaction is most useful in determining A) the
amount of energy catalysts required for biosynthesis or catabolism. B) the potential metabolic
reaction rate. C) whether there will be a requirement or production of energy. D) energy stored
in each compound. - ANS C whether there will be a requirement or production of energy
, Which is an example of a micronutrient? A) arginine B) inorganic phosphorous C) iron D)
vitamin B12 - ANS C iron
Aseptic technique refers to A) the microbial inoculum placed into a test tube or onto a Petri
plate. B) a series of practices to avoid contamination. C) the autoclave and other sterilizing
procedures. D) cleanliness in the laboratory. - ANS B a series of practices to avoid
contamination
To ensure growth of a newly discovered bacterium with unknown nutritional requirements, it
would be best to begin with a ________ medium rather than a ________ medium. A) complex /
minimal B) minimal / complex C) selective / complex D) selective / differential - ANS A
complex/minimal
If ΔG0ʹ is negative, the reaction is A) exergonic and requires the input of energy. B) endergonic
and requires the input of energy. C) exergonic and energy will be released. D) endergonic and
energy will be released. - ANS C exergonic and energy will be released
Activation energy is the energy A) required for a chemical reaction to begin. B) given off as the
products in a chemical reaction are formed. C) absorbed as ΔG0ʹ moves from negative to
positive. D) needed by an enzyme to catalyze a reaction without coenzymes. - ANS A required
for a chemical reaction to begin
A catalyst A) requires more reactants but makes the reaction rate faster. B) increases the
amount of reactants produced but does not change the rate. C) changes the rate of the reaction
but does not change the end amount of products. D) changes both the rate of a reaction and the
amount of the product that will be obtained as the reaction is completed. - ANS C changes the
rate of the reaction but does not change the end amount of products
The portion of an enzyme to which substrates bind is referred to as the A) substrate complex. B)
active site. C) catalytic site. D) junction of van der Waals forces. - ANS B active site
What is the difference between a coenzyme and a prosthetic group? A) Coenzymes are
essential for an enzymeʹs function and prosthetic groups only enhance its reaction rate. B)
Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective
enzymes. C) Coenzymes are organic cofactors and prosthetic groups are inorganic cofactors.
D) Coenzymes require additional ions to bind to enzymes but prosthetic groups are able to
directly interact with enzymes. - ANS B Coenzymes are weakly bound whereas prosthetic
groups are strongly bound to their respective enzymes.
If an oxidation reaction occurs A) simultaneous reduction of a different compound will also
occur, because electrons do not generally exist alone in solution. B) another oxidation reaction
will occur for a complete reaction, because one oxidation event is considered a half reaction. C)
a cell is undergoing aerobic respiration, because oxygen is being used. D) a reduction reaction
would not occur, because they are opposite reaction mechanisms. - ANS A simultaneous
The prokaryotic transport system that involves a substrate-binding protein, a
membrane-integrated transporter, and an ATP-hydrolyzing protein is A) the ABC transport
system. B) group translocation. C) symport. D) simple transport. - ANS A the ABC transport
system
The sum of all biosynthetic reactions in a cell is known as A) metabolism. B) anabolism. C)
catabolism. D) synthatabolism. - ANS B anabolism
Based on the functional roles of phosphate in various microbial metabolisms, which of the
following compounds most likely contain phosphate? A) organic compounds B) inorganic
compounds C) both organic and inorganic compounds D) neither organic nor inorganic
compounds - ANS C both organic and inorganic compounds
Which of the following would be used by a chemoorganotroph for energy? A) C2H3O2- B) H2
C) CO2 D) H+ - ANS A C2H3O2-
Which of the following statements is FALSE? A) Most bacteria are capable of using ammonia as
their sole nitrogen source. B) Some bacteria are able to use nitrates or nitrogen gas as their
nitrogen source. C) Most available nitrogen is in organic forms. D) Nitrogen is a major
component of proteins and nucleic acids. - ANS C most available nitrogen is in organic forms
All microorganisms require A) carbon, iron, and sodium. B) phosphorus, aluminum, and sodium.
C) calcium, potassium, and magnesium. D) phosphorus, selenium, and sulfur. - ANS D
phosphorus, selenium, and sulfur
Which element functions BOTH as an enzyme cofactor and as a stabilizer of ribosomes and
nucleic acids? A) iron B) hydrogen C) zinc D) magnesium - ANS D magnesium
Based on your understanding of metabolism, generalize when an enzymeʹs rate of activity can
be changed. A) before enzyme production B) during enzyme production C) after enzyme
production D) at any point—before, during, or after enzyme production - ANS C after enzyme
production
The change in Gibbs free energy for a particular reaction is most useful in determining A) the
amount of energy catalysts required for biosynthesis or catabolism. B) the potential metabolic
reaction rate. C) whether there will be a requirement or production of energy. D) energy stored
in each compound. - ANS C whether there will be a requirement or production of energy
, Which is an example of a micronutrient? A) arginine B) inorganic phosphorous C) iron D)
vitamin B12 - ANS C iron
Aseptic technique refers to A) the microbial inoculum placed into a test tube or onto a Petri
plate. B) a series of practices to avoid contamination. C) the autoclave and other sterilizing
procedures. D) cleanliness in the laboratory. - ANS B a series of practices to avoid
contamination
To ensure growth of a newly discovered bacterium with unknown nutritional requirements, it
would be best to begin with a ________ medium rather than a ________ medium. A) complex /
minimal B) minimal / complex C) selective / complex D) selective / differential - ANS A
complex/minimal
If ΔG0ʹ is negative, the reaction is A) exergonic and requires the input of energy. B) endergonic
and requires the input of energy. C) exergonic and energy will be released. D) endergonic and
energy will be released. - ANS C exergonic and energy will be released
Activation energy is the energy A) required for a chemical reaction to begin. B) given off as the
products in a chemical reaction are formed. C) absorbed as ΔG0ʹ moves from negative to
positive. D) needed by an enzyme to catalyze a reaction without coenzymes. - ANS A required
for a chemical reaction to begin
A catalyst A) requires more reactants but makes the reaction rate faster. B) increases the
amount of reactants produced but does not change the rate. C) changes the rate of the reaction
but does not change the end amount of products. D) changes both the rate of a reaction and the
amount of the product that will be obtained as the reaction is completed. - ANS C changes the
rate of the reaction but does not change the end amount of products
The portion of an enzyme to which substrates bind is referred to as the A) substrate complex. B)
active site. C) catalytic site. D) junction of van der Waals forces. - ANS B active site
What is the difference between a coenzyme and a prosthetic group? A) Coenzymes are
essential for an enzymeʹs function and prosthetic groups only enhance its reaction rate. B)
Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective
enzymes. C) Coenzymes are organic cofactors and prosthetic groups are inorganic cofactors.
D) Coenzymes require additional ions to bind to enzymes but prosthetic groups are able to
directly interact with enzymes. - ANS B Coenzymes are weakly bound whereas prosthetic
groups are strongly bound to their respective enzymes.
If an oxidation reaction occurs A) simultaneous reduction of a different compound will also
occur, because electrons do not generally exist alone in solution. B) another oxidation reaction
will occur for a complete reaction, because one oxidation event is considered a half reaction. C)
a cell is undergoing aerobic respiration, because oxygen is being used. D) a reduction reaction
would not occur, because they are opposite reaction mechanisms. - ANS A simultaneous
