Deck 13: Prokaryotes and Viruses

Question 1

Which of the following statements concerning nanotubes is FALSE?

A) They have a plasma membrane.
B) They are composed of cell wall material.
C) They contain cytoplasm.
D) They provide a network for the exchange of molecules.
E) They are indistinguishable from pili.

Answer 1

E

Question 2

In prokaryotes, poly-β-hydroxybutyric acid is a storage compound occurring:

A) in the nucleoid.
B) in the plasma membrane.
C) in the cell wall.
D) as inclusion bodies.
E) as fimbriae.

Answer 2

D

Question 3

By definition, autotrophs differ from heterotrophs in that autotrophs:

A) use inorganic compounds as an energy source.
B) use light as an energy source.
C) use carbon dioxide as their sole source of carbon.
D) obtain their carbon from dead organic matter.
E) obtain their energy from dead organic matter.

Answer 3

C

Question 4

Structures called _______ connect two cells and draw them together for DNA transfer.

A) pili
B) flagellin
C) flagella
D) fimbriae
E) nanotubes

Question 5

Which of the following statements about the ecological role of prokaryotes is FALSE?

A) Autotrophic species make major contributions to the global carbon balance.
B) Certain species fix atmospheric nitrogen.
C) Decomposers recycle materials from the bodies of dead organisms.
D) Certain bacteria degrade pesticides and other synthetic substances.
E) Certain prokaryotes are currently the most widely used method for cleaning up toxic dumps.

Question 6

The cell walls of gram-positive and gram-negative Bacteria differ in that gram-positive species have cell walls:

A) with less peptidoglycan.
B) of greater thickness.
C) consisting of two layers.
D) with a layer of lipopolysaccharides.
E) with a structure similar to that of the plasma membrane.

Question 7

Which of the following is the uptake of DNA by a prokaryotic cell from its environment?

A) binary fission
B) transduction
C) transformation
D) conjugation
E) budding

Question 8

The oldest known fossils of prokaryotes are found in rocks dated at about ______ years old.

A) 3.5 million
B) 35 million
C) 350 million
D) 3.5 billion
E) 35 billion

Question 9

Which of the following statements about prokaryotic endospores is FALSE?

A) They are dormant, resting cells.
B) They form when a population of cells begins to exhaust its food supply.
C) They greatly increase the survival capacity of the cell.
D) They are resistant to heat but not to desiccation.
E) They can remain viable for long periods.

Question 10

The glycocalyx is a:

A) type of bacterial plasmid.
B) convoluted infolding of the prokaryotic plasma membrane.
C) type of inclusion body in prokaryotic cells.
D) constituent of the cell wall of gram-positive Bacteria.
E) slimy or gummy substance coating the outer surface of the prokaryotic cell wall.

Question 11

Which of the following statements does NOT describe the plasma membrane of prokaryotes?

A) Like eukaryotic plasma membranes, it is a lipid bilayer.
B) Like eukaryotic plasma membranes, it contains proteins and sterols.
C) In aerobic species, it is the site of the electron transport chain.
D) In some photosynthetic species it is the site of photosynthesis.
E) It has attachment sites for daughter chromosomes during cell division.

Question 12

Bacterial fermentation of lactose is associated with the production of:

A) streptomycin.
B) tetracycline.
C) cheese.
D) vinegar.
E) amino acids.

Question 13

In the photosynthetic purple bacteria, photosynthesis occurs in the:

A) pili.
B) glycocalyx.
C) cell wall.
D) nucleoid.
E) plasma membrane.

Question 14

Prokaryotic flagella differ from eukaryotic flagella in that prokaryotic flagella:

A) are surrounded by a plasma membrane.
B) consist of microtubules.
C) consist of subunits of flagellin.
D) are long, slender appendages.
E) are involved in motility.

Question 15

A coccus has a ______ shape.

A) spherical
B) spiral
C) cylindrical
D) curved
E) triangular

Question 16

Prokaryotes that use inorganic compounds rather than light as an energy source are called:

A) heterotrophs.
B) chemosynthetic autotrophs.
C) photosynthetic autotrophs.
D) psychrophiles.
E) saprotrophs.

Question 17

Which of the following statements concerning biofilms is FALSE?

A) They consist of assemblages of cells enclosed in a matrix of molecules.
B) They are composed of bacteria but not archaea.
C) They require communication and signaling among cells.
D) An example is the film that develops on unbrushed teeth.
E) They increase the chances for survival of cells in the biofilm.

Question 18

Prokaryotes that can grow in the presence of oxygen, even though they cannot use oxygen, are called:

A) facultative anaerobes.
B) facultative aerobes.
C) photosynthetic autotrophs.
D) psychrophiles.
E) thermophiles

Question 19

Which of the following processes is NOT a type of lateral gene transfer in prokaryotes?

A) binary fission
B) transduction
C) transformation
D) conjugation
E) horizontal gene transfer

Question 20

The cell walls of Bacteria differ from those of Archaea and eukaryotes in that the cell walls of Bacteria contain:

A) cellulose.
B) sterols.
C) peptidoglycans.
D) phospholipids.
E) poly-β-hydroxybutyric acid.

Question 21

Which of the following statements concerning archaeans is FALSE?

A) Some inhabit hostile environments.
B) Some inhabit soils.
C) Some are pathogenic.
D) They are a major component of the oceanic picoplankton.
E) They can be divided into four groups.

Question 22

______ are archaeans living in regions of very high salt concentration.

A) Mycoplasmas
B) Extreme thermophiles
C) Members of the genus Thermoplasma
D) Extreme halophiles
E) Methanogens

Question 23

Stromatolites are produced when cyanobacteria:

A) bind calcium-rich sediments.
B) produce sheaths covered with ice crystals.
C) react with the minerals in hot springs.
D) interact with fur.
E) interact with the roots of higher plants.

Question 24

A viral disease of plants in which the symptoms are small, light-colored flecks intermingled with the normal green of leaves and fruit is called:

A) ring spot.
B) yellows.
C) canker.
D) leaf roll.
E) mosaic.

Question 25

An akinete is a ______ of cyanobacteria.

A) photosynthetic pigment
B) filamentous fragment
C) storage compound
D) resistant spore
E) pigment

Question 26

______ are probably the smallest organisms capable of independent growth.

A) Mycoplasmas
B) Purple bacteria
C) Green sulfur bacteria
D) Cyanobacteria
E) Prochlorophytes

Question 27

What prokaryotes lack a cell wall and cause highly destructive diseases such as X-disease of peach?

A) prochlorophytes
B) cyanobacteria
C) purple nonsulfur bacteria
D) green nonsulfur bacteria
E) phytoplasmas

Question 28

A disease in which bacteria invade the vessels of the xylem and interfere with the movement of water and minerals is a:

A) blight.
B) soft rot.
C) wilt.
D) gall.
E) spot.

Question 29

______ are photosynthetic prokaryotes that contain chlorophylls a and b and carotenoids but lack phycobilins.

A) Mycoplasmas
B) Purple and green bacteria
C) Mycoplasma-like organisms
D) Cyanobacteria
E) Prochlorophytes

Question 30

Phylogenetic analysis indicates that there are at least ______ major lineages of Bacteria.

A) 4
B) 5
C) 8
D) 17
E) 20

Question 31

Which of the following statements about the environmental ranges of cyanobacteria is FALSE?

A) Most species are symbiotic.
B) Some species grow in hot springs.
C) Some species grow in Antarctic lakes.
D) Some species grow in acidic waters.
E) Some species grow in the fur of polar bears.

Question 32

The heterocysts of cyanobacteria are most closely associated with:

A) sporulation.
B) nitrogen fixation.
C) photosynthesis.
D) gliding movements.
E) buoyancy.

Question 33

Which group of photosynthetic prokaryotes has bacteriochlorophyll and only one photosystem?

A) mycoplasmas
B) purple and green bacteria
C) spiroplasmas
D) cyanobacteria
E) prochlorophytes

Question 34

Which of the following statements about viruses is FALSE?

A) Practically every kind of organism can be infected by a virus.
B) The simplest viruses consist of a nucleic acid surrounded by a capsid.
C) Some viruses have an RNA genome.
D) Outside its host cell, a virion has a slow metabolism.
E) Some viruses contain double-stranded DNA.

Question 35

Which of the following statements concerning plant viral infections is FALSE?

A) The viruses penetrate the cell wall.
B) Once inside the cell, the virion sheds its capsid.
C) The viral nucleic acid takes over the genetic machinery of the host cell.
D) Additional nucleic acids are produced.
E) Viral nucleic acids and proteins are assembled into additional virus particles.

Question 36

The great majority of viruses have a genome composed of:

A) single-stranded RNA.
B) single-stranded DNA.
C) double-stranded RNA.
D) double-stranded DNA.
E) RNA and DNA.

Question 37

Which group of archaeans lacks a cell wall?

A) mycoplasmas
B) extreme thermophiles
C) members of the genus Thermoplasma
D) extreme halophiles
E) methanogens

Question 38

The strict anaerobes residing in the digestive tracts of cattle are:

A) mycoplasmas.
B) extreme thermophiles.
C) members of the genus Thermoplasma.
D) extreme halophiles.
E) methanogens.

Question 39

In the process of nitrogen fixation:

A) Photosystem II occurs but not Photosystem I.
B) cyclic photophosphorylation does not occur.
C) oxygen is produced as a waste product.
D) nitrogen gas is converted to amino acids.
E) nitrogen gas is converted to ammonium.

Question 40

Citrus stubborn disease is caused by a:

A) green bacterium.
B) purple nonsulfur bacterium.
C) spiroplasma.
D) cyanobacterium.
E) prochlorophyte.

Question 41

Prokaryote cells contain a nucleoid but not a nuclear envelope.

Question 42

Transduction is a type of lateral gene transfer.

Question 43

Psychrophiles are prokaryotes that have very high temperature optima.

Question 44

In prokaryotes, poly-β-hydroxybutyric acid rather than glycogen is the major storage substance.

Question 45

Which of the following statements concerning the hypersensitive response is FALSE?

A) It is a response to infection by different types of pathogens.
B) It is usually mediated by recessive genes.
C) It includes host cell death at the infection site.
D) It includes the accumulation of antimicrobial molecules.
E) It inhibits pathogen movement at the edge of the lesion.

Question 46

The purple and green bacteria are photosynthetic bacteria that grow only under anaerobic conditions.

Question 47

Bacteriophages are responsible for the process of transformation.

Question 48

The prokaryotes are the most dominant and successful organisms on Earth.

Question 49

Viroids consist only of a:

A) protein capsid.
B) linear DNA molecule.
C) circular DNA molecule.
D) linear RNA molecule.
E) circular RNA molecule.

Question 50

The smallest known photosynthetic organism is a prochlorophyte called Prochlorococcus.

Question 51

Stromatolites are layered chalk deposits produced by colonies of Trichodesmium.

Question 52

A bacillus has a spherical shape.

Question 53

Some bacteria are capable of fixing atmospheric nitrogen to form nitrogen-containing compounds.

Question 54

In the process of conjugation, DNA is transferred from one cell to another via pili.

Question 55

Biofilms consist of bacteria and archaea enclosed in a matrix of polysaccharides, proteins, and DNA.

Question 56

In contrast to other cellular components, the flagellum found in prokaryotic cells is identical in structure to that found in eukaryotic cells.

Question 57

One method by which prokaryotes reproduce asexually is binary fission.

Question 58

A viral capsid is a:

A) protein coat.
B) strand of DNA.
C) strand of RNA.
D) plasma membrane.
E) type of organelle.

Question 59

Pseudomonas aeruginosa forms biofilms in the airways of the lungs.

Question 60

Movement proteins facilitate the movement of viruses:

A) through plasmodesmata.
B) through vessels.
C) through sieve tubes.
D) across the plasma membrane.
E) across the nuclear envelope.

Question 61

Many species of Archaea are pathogenic to plants.

Question 62

Mycoplasmas have cell walls containing peptidoglycan.

Question 63

A virus can reproduce inside and outside a host cell.

Question 64

Within an infected plant, viruses move from cell to cell through plasmodesmata in a process facilitated by movement proteins.

Question 65

In flowering plants, phytoplasmas are generally confined to the xylem.

Question 66

Viruses are spread from diseased to healthy plants primarily by bacteria.

Question 67

The great majority of plant viruses have a genome composed of single-stranded RNA.