14 A the partial oxidation of glucose with organic molecules serving as electron acceptors B the complete catabolism of glucose to CO2 and H2O C the partial reduction of glucose to pyruv
Trang 1Test Bank for Microbiology An Introduction 11th Edition
by Tortora
Chapter 5
Exam
Name _
MULTIPLE CHOICE Choose the one alternative that best completes the statement or answers the question 1) Which of the following compounds is NOT an enzyme? 1) A) coenzyme A B) cellulase C) ?-galactosidase D)
sucrase E) dehydrogenase Answer: A
Explanation: A) B) C) D) E) 2) Which of the following statements about
photophosphorylation is FALSE? 2) A) Energy from oxidation reactions is used to generate ATP from ADP B) Light liberates an electron from
chlorophyll C) It occurs in photosynthesizing cells D) The oxidation of carrier molecules releases energy E) It requires CO2 Answer: E
Explanation: A) B) C) D) E) 3) Gallionella bacteria can get energy from the reaction Fe2+ Fe3+ This reaction is an example of 3) A) the Calvin-Benson cycle B) reduction C) fermentation D) oxidation E) photophosphorylation Answer: D
Explanation: A) B) C) D) E) 1
4)
A bacterial culture grown in a glucose-peptide medium causes the pH to
increase The bacteria are
most likely 4) A) oxidizing the glucose B) using the peptides C) fermenting the glucose D) not growing Answer: B
Explanation: A) B) C) D) 5) Which of the following statements about substrate-level phosphorylation is FALSE? 5) A) It occurs in glycolysis B)
It involves the direct transfer of a high-energy phosphate group from an
intermediate
metabolic compound to ADP C)
The oxidation of intermediate metabolic compounds releases energy that is used to generate
ATP D) No final electron acceptor is required E) It occurs in the Krebs cycle
Trang 2Answer: C
Explanation: A) B) C) D) E) 6) Which organism is NOT correctly matched to
its energy source? 6) A) chemoautotroph – Fe2+
B) chemoheterotroph – glucose C) chemoautotroph-NH3
D) photoheterotroph – light E) photoautotroph –
CO2 Answer: E
Explanation: A) B) C) D) E) 7) Which of the following is the best definition of
oxidative phosphorylation? 7) A)
A proton gradient allows hydrogen ions to flow back into the cells through
transmembrane
protein channels, releasing energy that is used to generate ATP B)
Electrons are passed through a series of carriers to O2
C) Electrons are passed through a series of carriers to an organic compound
D) ATP is directly transferred from a substrate to ADP Answer:
A Explanation: A) B) C) D) 2
8) Which of the following statements regarding the glycolysis pathway is
FALSE? 8) A) Two NADH molecules are generated B) One molecule of ATP
is expended C) Two molecules of water are generated D) Two pyruvate
molecules are generated E) Four ATP molecules are generated via
substrate-level phosphorylation Answer: B
Explanation: A) B) C) D)
E) Figure 5.6
9)
The rates of O2 and glucose consumption by a bacterial culture are shown in
Figure 5.6 Assume a
bacterial culture was grown in a glucose medium without O2 Then O2
was added at the time
B) these bacteria cannot grow anaerobically C) aerobic metabolism is more
efficient than fermentation D) these bacteria get more energy anaerobically
Answer: C
Explanation: A) B) C) D) 3
10) If a cell is starved for ATP, which of the following pathways would most
likely be shut down? 10) A) glycolysis B) Kreb’s cycl pathway D) Krebs cycle and
glycolysis Answer: C
Explanation: A) B) C) D)
Figure 5.7
11)
The graph at the left in Figure 5.7 shows the reaction rate for an enzyme at
its optimum
temperature Which graph shows enzyme activity at a higher temperature?
Trang 311) A) a B) b C) c D)
d Answer: B
Explanation: A) B) C) D) 12)
Which of the following statements are true?
1-Electron carriers are located at ribosomes
2-ATP is a common intermediate between catabolic and anabolic pathways 3-ATP is used for the long-term storage of energy and so is often found in storage granules
4-Anaerobic organisms are capable of generating ATP via respiration
5-ATP can be generated by the flow of protons across protein channels
12) A) 1, 2, 3 B) 1, 3, 4 C) 2, 3, 5 D) 2, 4, 5 E) All of the statements are
true Answer: D
Explanation: A) B) C) D) E) 4
13) Fatty acids are oxidized in 13) A) the pentose phosphate pathway B) the electron transport chain C) the Entner-Doudoroff pathway D) the Krebs
cycle E) glycolysis Answer: D
Explanation: A) B) C) D) E) 14) Which of the following is the best definition
of fermentation? 14) A) the partial oxidation of glucose with organic
molecules serving as electron acceptors B) the complete catabolism of
glucose to CO2 and H2O
C) the partial reduction of glucose to pyruvic acid D) the production of
energy by oxidative-level phosphorylation E) the production of energy by both substrate and oxidative phosphorylation Answer: A
Explanation: A) B) C) D) E) 15) What is the fate of pyruvic acid in an
organism that uses aerobic respiration? 15) A) It is reduced to lactic acid B) It
is catabolized in glycolysis C) It reacts with oxaloacetate to form citrate D) It
is converted into acetyl CoA E) It is oxidized in the electron transport chain Answer: D
Explanation: A) B) C) D) E) 16) A urease test is used to identify
Myobacterium tuberculosis because 16) A) M bovis can cause tuberculosis B) some bacteria reduce nitrate ion C) urea accumulates during tuberculosis D) M tuberculosis produces urease E) urease is a sign of tuberculosis
Answer: D Explanation: A) B) C) D) E) 5
17) In green and purple bacteria, electrons to reduce CO2 can come from 17) A) H2O B) H2S C) C6H12O6
D) chlorophyll E) CO2
Answer: B
Explanation: A) B) C) D) E) 18) Which of the following uses CO2 for carbon and H2 for energy? 18) A) chemoheterotroph B) chemoautotroph C)
photoheterotroph D) photoautotroph Answer: B
Explanation: A) B) C) D) 19) Which of the following is NOT necessary for
Trang 4respiration? 19) A) quinones B) flavoproteins C) oxygen D) cytochromes E)
a source of electrons Answer: C
Explanation: A) B) C) D) E) 20) Which of the following statements regarding the Entner-Doudoroff pathway is TRUE? 20) A) ATP is generated B) NADH is generated C) It involves the pentose phosphate pathway D) It involves
glycolysis E) NADH and ATP are generated Answer: A Explanation: A) B) C) D) E) 6
Figure 5.8
D) ATP synthase E) cytoplasm Answer: B
Explanation: A) B) C) D) E) 22) Cyanobacteria are a type of 22)
A) photoheterotroph B) chemoautotroph C) chemoheterotroph
D) photoautotroph Answer: D
Explanation: A) B) C) D) 23) A strictly fermentative bacterium produces
energy 23) A) by aerobic respiration only B) only in the absence of oxygen C) by glycolysis only D) only in the presence of oxygen E) by fermentation or aerobic respiration Answer: C
Explanation: A) B) C) D) E)
7 Figure 5.4
24) How is ATP generated in the reaction shown in Figure 5.4? 24)
A) photophosphorylation B) oxidative phosphorylation C)
substrate-level phosphorylation D) fermentation E) glycolysis Answer: C
Explanation: A) B) C) D) E) 25)
Which one of the following would you predict is an allosteric inhibitor of
the Krebs cycle enzyme,
?-ketoglutarate dehydrogenase? 25) A) ?-ketoglutaric acid B) ADP C) NADH D) citric acid E) NAD+
Answer: C
Explanation: A) B) C) D) E) 26) In noncyclic photophosphorylation, O2
is released from 26) A) H2O B) chlorophyll C) sunlight D) CO2
E) C6H12O6
Answer: A
Explanation: A) B) C) D) E) 8
27) Which of the following uses glucose for carbon and energy? 27) A)
chemoheterotroph B) photoheterotroph C) photoautotroph D)
chemoautotroph Answer: A
Explanation: A) B) C) D)
Figure 5.3
28)
How would a noncompetitive inhibitor interfere with a reaction involving the
Trang 5enzyme shown in
Figure 5.3? 28) A) It would bind to a B) It would bind to b C) It would bind to
c D) It would bind to d E) The answer cannot be determined based on the information provided Answer: B
Explanation: A) B) C) D) E) 9
Figure 5.1
29) Which compound is being reduced in the reaction shown in Figure 5.1? 29) A) NADH B) NAD+
C) ?-ketoglutaric acid and NAD+
D) isocitric acid and ?-ketoglutaric acid E) NADH and isocitric acid Answer: B Explanation: A) B) C) D) E) 10
Figure 5.8
30) Refer to Figure 5.8 In aerobic respiration, where is water formed? 30) A)
a B) b C) c D) d E) e
Answer: D
Explanation: A) B) C) D) E) 11
Figure 5.2
31) What type of reaction is in Figure 5.2? 31) A) reduction B) transamination C) dehydrogenation D) decarboxylation E) oxidation Answer: B Explanation: A) B) C) D) E) 32) Which of the following statements about beta oxidation is FALSE? 32) A) It is a method of catabolizing fatty acids B) It is a step in glycolysis C) It is used in petroleum degradation D) It involves the formation
of acetyl-CoA E) It involves the formation of 2-carbon units Answer: B
Explanation: A) B) C) D) E) 12
Figure 5.8
33) What is the most acidic place in Figure 5.8? 33) A) a B) b C) c D) d E) e Answer: A
Explanation: A) B) C) D) E) 34)
Which of the following is TRUE about this reaction?
NO3
-+ 2H+
Pseudomonas NO2
– + H2O
Nitrate ion Nitrite ion
34) A) This process occurs anaerobically B) This process requires O2 C) This process requires the electron transport system D) This process requires light E) This process requires O2 and the electron transport system Answer: A
Explanation: A) B) C) D) E) 13
35)
Trang 6Microorganisms that catabolize sugars into ethanol and hydrogen gas would most likely be
categorized as 35) A) aerobic respirers B) homolactic fermenters C) alcohol fermenters D) anaerobic respirers E) heterolactic fermenters Answer: E Explanation: A) B) C) D) E)
Figure 5.8
C) protons D) energy E) electrons Answer: C
Explanation: A) B) C) D) E) 37) Which of the following statements regarding metabolism is FALSE? 37) A) Heat may be released in both anabolic and catabolic reactions B) ADP is formed in anabolic reactions C) ATP is
formed in catabolic reactions D) Anabolic reactions are degradative
Answer: D Explanation: A) B) C) D) 14
38) The advantage of the pentose phosphate pathway is that it produces all
of the following EXCEPT 38) A) precursors for the synthesis of glucose B) NADPH C) three ATPs D) precursors for the synthesis of amino acids E) precursors for nucleic acids Answer: C
Explanation: A) B) C) D) E) 39) Which of the following has
bacteriochlorophylls and uses alcohols for carbon? 39) A) chemoautotroph B) photoautotroph C) photoheterotroph D) chemoheterotroph Answer: C Explanation: A) B) C) D) 40)
Assume you are growing bacteria on a lipid medium that started at pH 7 The action of bacterial
lipases should cause the pH of the medium to 40) A) stay the same
B) decrease C) increase Answer: B
Explanation: A) B) C) 15
Figure 5.8
41) In Figure 5.8, where is ATP produced? 41) A) a B) b C) c D) d E)
e Answer: E
Explanation: A) B) C) D) E) 42)
An enzyme, citrate synthase, in the Krebs cycle is inhibited by ATP This is
an example of all of the
following EXCEPT 42) A) feedback inhibition B) competitive inhibition
C) noncompetitive inhibition D) allosteric inhibition Answer: B
Explanation: A) B) C) D) 16
Figure 5.5
43)
Which of the graphs in Figure 5.5 best illustrates the activity of an enzyme that is saturated with
substrate? 43) A) a B) b C) c D) d E) e
Answer: C
Trang 7Explanation: A) B) C) D) E) 44)
Assume you are working for a chemical company and are responsible for
growing a yeast culture
that produces ethanol The yeasts are growing well on the maltose medium
but are not producing
alcohol What is the most likely explanation? 44) A) The maltose is toxic B)
O2 is in the medium C) The temperature is too low D) The temperature is too
high E) Not enough protein is provided Answer: B
Explanation: A) B) C) D) E) 45) Which of the following statements about
B) It yields lower amounts of ATP when compared to aerobic respiration C)
It involves the reduction of an organic final electron acceptor D) It generates
ATP E) It requires cytochromes Answer: C
Explanation: A) B) C) D) E) 17
TRUE/FALSE Write ‘T’ if the statement is true and ‘F
46) An apoenzyme that loses its coenzyme subunit will be non-functional 46)
Answer: True False Explanation: 47) Glycolysis is utilized by cells in both
respiration and fermentation 47) Answer: True False Explanation: 48) The
pentose phosphate pathway can be characterized as an anabolic pathway
48) Answer: True False Explanation: 49) Both respiration and photosynthesis
require the use of an electron transport chain 49) Answer: True False
Explanation: 50) Both respiration and photosynthesis use water molecules for
the donation of hydrogen ions 50) Answer: True False Explanation: 51)
Catabolic reactions are generally degradative and hydrolytic 51) Answer:
True False Explanation: 52)
Once an enzyme has converted substrates into products, the active site
reverts back to its original
form 52) Answer: True False Explanation: 53)
The use of enzymes is necessary to increase the activation energy
requirements of a chemical
reaction 53) Answer: True False Explanation: 54) Carbon fixation occurs
during the light-independent phase of photosynthesis 54) Answer: True False
Explanation: 55) In general, ATP is generated in catabolic pathways and
expended in anabolic pathways 55) Answer: True False Explanation: ESSAY
Write your answer in the space provided or on a separate sheet of paper 56)
Rhodopseudomonas is an anaerobic photoautotroph that uses organic
compounds as an electron donor It is also
capable of chemoheterotrophic metabolism Diagram the metabolic
pathways of this bacterium Answer: 18
57)
Streptococcus lacks an electron transport chain How does this bacterium
Trang 8reoxidize NADH? Where is the NADH
formed? Answer: 58) Differentiate the following two laboratory tests: starch hydrolysis and starch fermentation Answer: 59)
You look in the refrigerator and find some orange drink you had forgotten
was there The drink now has an
the drink? Answer: 60) Compare and contrast photophosphorylation and
oxidative phosphorylation Answer: 19
Answer Key
Testname: C5
1) A
2) E
3) D
4) B
5) C
6) E
7) A
8) B
9) C
10) C
11) B
12) D
13) D
14) A
15) D
16) D
17) B
18) B
19) C
20) A
21) B
22) D
23) C
24) C
25) C
26) A
27) A
28) B
29) B
30) D
31) B
Trang 932) B
33) A
34) A
35) E
36) C
37) D
38) C
39) C
40) B
41) E
42) B
43) C
44) B
45) C
46) TRUE 47) TRUE 48) FALSE 49) TRUE 50) FALSE