Prokaryotes And Viruses Ch.13 Complete Test Bank nan

Chapter 13: Prokaryotes and Viruses

Multiple-Choice Questions

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

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.

In the photosynthetic purple bacteria, photosynthesis occurs in the:

a. pili.

b. glycocalyx.

c. cell wall.

d. nucleoid.

e. plasma membrane.

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.

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.

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.

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.

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.

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

a. pili

b. flagellin

c. flagella

d. fimbriae

e. nanotubes

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.

A coccus has a ______ shape.

a. spherical

b. spiral

c. cylindrical

d. curved

e. triangular

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.

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

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

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.

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.

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.

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

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.

Bacterial fermentation of lactose is associated with the production of:

a. streptomycin.

b. tetracycline.

c. cheese.

d. vinegar.

e. amino acids.

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

a. 4

b. 5

c. 8

d. 17

e. 20

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.

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.

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.

The heterocysts of cyanobacteria are most closely associated with:

a. sporulation.

b. nitrogen fixation.

c. photosynthesis.

d. gliding movements.

e. buoyancy.

An akinete is a ______ of cyanobacteria.

a. photosynthetic pigment

b. filamentous fragment

c. storage compound

d. resistant spore

e. pigment

______ 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

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

a. mycoplasmas

b. purple and green bacteria

c. spiroplasmas

d. cyanobacteria

e. prochlorophytes

______ are probably the smallest organisms capable of independent growth.

a. Mycoplasmas

b. Purple bacteria

c. Green sulfur bacteria

d. Cyanobacteria

e. Prochlorophytes

Citrus stubborn disease is caused by a:

a. green bacterium.

b. purple nonsulfur bacterium.

c. spiroplasma.

d. cyanobacterium.

e. prochlorophyte.

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

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.

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.

______ 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

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.

Which group of archaeans lacks a cell wall?

a. mycoplasmas

b. extreme thermophiles

c. members of the genus Thermoplasma

d. extreme halophiles

e. methanogens

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.

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.

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.

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.

A viral capsid is a:

a. protein coat.

b. strand of DNA.

c. strand of RNA.

d. plasma membrane.

e. type of organelle.

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.

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.

Viroids consist only of a:

a. protein capsid.

b. linear DNA molecule.

c. circular DNA molecule.

d. linear RNA molecule.

e. circular RNA molecule.

True-False Questions

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

Prokaryote cells contain a nucleoid but not a nuclear envelope.

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

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

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

A bacillus has a spherical shape.

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

One method by which prokaryotes reproduce asexually is binary fission.

Transduction is a type of lateral gene transfer.

Bacteriophages are responsible for the process of transformation.

Psychrophiles are prokaryotes that have very high temperature optima.

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

Pseudomonas aeruginosa forms biofilms in the airways of the lungs.

Stromatolites are layered chalk deposits produced by colonies of Trichodesmium.

The smallest known photosynthetic organism is a prochlorophyte called Prochlorococcus.

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

Mycoplasmas have cell walls containing peptidoglycan.

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

Many species of Archaea are pathogenic to plants.

A virus can reproduce inside and outside a host cell.

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

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

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

Viroid RNA is replicated in the cytoplasm of the host cell then used as a template to synthesize a strand of DNA.

Essay Questions

1. Introduction; pp. 256–257; moderate

What features are responsible for the dominance and success of prokaryotes?

2. Characteristics of the Prokaryotic Cell; p. 258; moderate

Describe the differences in cell wall structure between gram-positive and gram-negative Bacteria.

3. Characteristics of the Prokaryotic Cell; pp. 258-259; moderate

How are prokaryotic flagella, fimbriae, and pili different? How are they similar?

4. Diversity of Form; p. 259; moderate

Describe the variety of cell shapes and growth forms in prokaryotes.

5. Reproduction and Gene Exchange; pp. 259–261; moderate

Compare and contrast the processes of binary fission, conjugation, transduction, and transformation.

6. Metabolic Diversity; pp. 262-263; moderate

Discuss some of the ways in which prokaryotes are (a) important to the functioning of ecosystems and (b) used commercially.

7. Bacteria; pp. 263–266; moderate

Describe some of the environments occupied by cyanobacteria. What cellular structures facilitate adaptation?

8. Bacteria; p. 265; moderate

What is meant by “nitrogen fixation” and what is its importance? What structures are present in cyanobacteria that facilitate this process?

9. Archaea; pp. 269–270; moderate

What are the four main groups of Archaea? What features do they have in common? How do they differ?

10. Viruses; p. 272; moderate

Discuss the variations observed in the viral genome. What is the most common composition among plant viruses?

11. Viruses; pp. 272-275; moderate

Discuss the ways in which a virus enters a host cell and then multiplies within it. How do new viruses then move from that cell to other parts of the host plant?

12. Viruses; p. 275; moderate

What is a viroid, and how does it differ from a virus? In what ways are viroids economically important?