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