,CHAPTER 1: Microbial Life: Origin and Discovery
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MULTIPLE CHOICE
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1. Viruses are: w
a. infectious agents that infect multi-cellular organisms
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b. noncellular particles that take over the metabolism of a cell to generate more
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virus particles
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c. pathogens that replicate in complex growth media w w w w w w
d. cellular particles that belong to the archaea domain
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e. microbes that consist of lipid membrane enclosed genomes
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ANS: B DIF:
w Easy REF: 1.1 w TOP: I.A | I.B w w w
MSC: Remembering w
2. Analysis of DNA sequences reveals:
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a. the ancient convergence of two cell types, i.e., prokaryotes and
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eukaryotes
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b. prokaryotes and eukaryotes evolved from a common ancestral cell
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c. that bacteria share common ancestor with archaea, but not with eukarya
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d. prokaryotes are cells with a nucleus w w w w w
e. the genome of Haemophilus influenzae has about 2 billion base pairs
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ANS: B DIF:
w Easy REF: 1.1 w TOP: I.A | I.B w w w
MSC: Remembering w
3. Which of these groups are considered to be microbes but NOT considered to be cells?
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a. viruses d. protists
b. bacteria e. filamentous fungi w
c. archaea
ANS: A DIF:
w Easy REF: 1.1 w TOP: I.A.i w
MSC: Remembering w
4. A microbe is commonly defined as:
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a. a virus that requires a microscope to be seen
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b. a bacterium that requires a microscope to be seen
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c. a single-cellular prokaryote that requires a microscope to be
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seen w
d. a multicellular eukaryote that requires a microscope to be seen
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e. a living organism that requires a microscope to be seen
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ANS: E DIF:
w Easy REF: 1.1 w TOP: I.A.i | I.A.ii
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MSC: Remembering w
5. Which one of the following statements regarding microbial cells is NOT true?
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a. Microbial cells acquire food, gain energy to build themselves, and respond
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to environmental change.
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, b. Most single-celled organisms require a microscope to render them visible, but
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some
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bacterial cells are large enough to be seen with naked eyes.
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c. Microbes function as individual entities.w w w w
d. Many microbes form complex multicellular assemblages.
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e. Viruses are not considered as microbial cells.
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ANS: C w DIF: Easy REF: 1.1 w TOP: I.A.i | I.A.ii
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MSC: Remembering
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6. Which of the following statements is FALSE?
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a. A genome is the total genetic information contained in an organism’s chromosomal
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DNA.
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b. If a microbe’s genome includes genes for nitrogenase, that microbe probably can fix
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nitrogen.
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c. By comparing DNA sequences of different organisms, we can figure out how closely
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related they are.
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d. Fred Sanger developed the first applicable DNA sequencing method.
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e. Fred Sanger completed the sequences of Haemophilus influenzae.
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ANS: E w DIF: Easy REF: 1.1 w TOP: I.B w
MSC: Remembering
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7. The first cellular genomes to be sequenced were those of:
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a. humans d. prions
b. bacteria e. fungi
c. viruses
ANS: B w DIF: Easy REF: 1.1 w TOP: I.B.iw
MSC: Remembering
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8. The environment of early Earth may have contained all of the following EXCEPT:
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a. ferrous iron w d. oxygen
b. methane e. hydrogen gas w
c. ammonia
ANS: D w DIF: Easy REF: Special Topic 1.1 w w w
TOP: II.D w MSC: Remembering w
9. The development of the theory of the ―RNA world‖ resulted from the discovery of:
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a. archaea d. ribozymes
b. prions e. endosymbionts
c. bacteria
ANS: D w DIF: Medium REF: Special Topic 1.1 w w w
TOP: II.D w MSC: Remembering w
10. Which microbes may resemble those of the earliest life forms?
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a. archaea d. cyanobacteria
b. photosynthetic algae e. protists w
c. viruses
ANS: A w DIF: Medium REF: Special Topic 1.1 w w w
TOP: II.D w MSC: Remembering w
11. Early metabolism may have been catalyzed by:
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