Question 1

All known methanogens are found in the domain ___.

Accepted Answer

archaea

Question 2

From which area would you be able to isolate the bacterium Halobacterium?

Accepted Answer

A)   the Pacific ocean
B)   the Indian ocean
C)   Lake Michigan
D)   the Great Salt Lake
E)   the Mediterranean Sea D

Question 3

You would be able to find methanogens in all of the following environments EXCEPT:

Accepted Answer

A)   the rumen of bovines.
B)   the bottom of a swamp.
C)   a well aerated aquifer.
D)   sediments from a freshwater lake.
E)   the benthic region of the ocean. C

Question 4

Why did Woese and Fox use rRNA gene sequences to compare the phylogenetic relatedness between microbes?

Accepted Answer

The answer of Why did Woese and Fox use rRNA...

Question 5

The secondary structure and amino acid composition of proteins from hyperthermophiles differ somewhat from proteins in mesophiles.What would you expect to find in thermophiles?

Accepted Answer

A)   More β-sheets and the amino acids tyrosine and arginine.
B)   More α-helices and the amino acids tyrosine and arginine.
C)   More β-sheets and the amino acids cysteine and serine.
D)   More β-sheets and the amino acids glycine and glutamate.
E)   More α-helices and the amino acids cysteine and serine.

Question 6

What is the specific action of bacteriorhodopsin?

Accepted Answer

A)   Modification of vitamins for use in metabolism.
B)   Assembles ADP and phosphate to make ATP.
C)   Binds glucose and other sugars in the cell.
D)   Facilitates the movement of glucose across the cell membrane.
E)   Produces proton motive force using light energy.

Question 7

What are chaperonins ("molecular chaperones")?

Accepted Answer

A)   Channels in the membrane for protein secretion.
B)   Proteins used for the secretion of other proteins.
C)   Proteins used for the correct folding of other proteins.
D)   Proteins involved in the regulation of gene expression at the level of transcription.
E)   Sensory proteins found in the cytoplasmic membrane to sense various environmental signals.

Question 8

Some archaeal cells contain pseudopeptidoglycan as their major cell wall component.What is this material composed of?

Accepted Answer

A)   Lipids and proteins.
B)   Sugar polymers cross-linked via a peptide bridge.
C)   Sugar polymers that are linked to lipids via an ether bond.
D)   Proteins liked together via a glycosidic bond.
E)   Lipids cross-linked via a peptide bridge.

Question 9

All members of the Archaea live in extreme environments.

Accepted Answer

A) True 
 B)False

Question 10

Why might the process of chemotaxis in the archaeon Halobacterium be similar to chemotaxis in Bacteria?

Accepted Answer

A)   Similar proteins in the chemotaxis signaling pathway are found in both Halobacterium and Bacteria.
B)   The flagellin protein is almost identical in sequence for both Halobacterium and Bacteria.
C)   Genes that encode proteins for flagellum assembly are found in both Halobacterium and Bacteria.
D)   Both Halobacterium and Bacteria use ATP to turn the flagellum.
E)   Flagellum assemble is identical in both Halobacterium and Bacteria.

Question 11

Besides the methanogens and the halophiles,the phylum Euryarchaeota contains many thermophiles and hyperthermophiles.Most of these are also classified as _____ .

Accepted Answer

A)   halophiles
B)   psychrophiles
C)   barophiles
D)   mesophiles
E)   acidophiles

Question 12

Members of the archaeal phylum Euryarchaeota are similar in their rRNA gene sequence but differ greatly in their metabolic characteristics.

Accepted Answer

A) True 
 B)False

Question 13

Evidence clearly shows that Archaea are direct descendants of the earliest life forms.

Accepted Answer

A) True 
 B)False

Question 14

How does the Archaea cytoplasmic membrane differ- from the Bacteria membrane?

Accepted Answer

A)   The Archaeal membrane contains cholesterol.
B)   The Archaeal membrane contains no proteins.
C)   The Archaeal membrane is comprised of fatty acids attached to glycerol phosphate by an ester linkage.
D)   The Archaeal membrane is comprised of isoprenoids attached to glycerol phosphate by an ether linkage.
E)   The Archaeal membrane gives the cell its characteristic shape.

Question 15

Many cultured and characterized strains from the phylum Crenarchaeota were isolated from _____ .

Accepted Answer

A)   the ocean
B)   freshwater lakes
C)   thermal hot springs
D)   dry soil
E)   sea ice

Question 16

Which member of the Archaea domain is a parasite of the archaeon Ignicoccus hospitalis and has one of the smallest genomes of all living microbes?

Accepted Answer

A)   Pyrolobus fumarii
B)   Thermoplasma acidophilum
C)   Nanoarchaeum equitans
D)   Nitrosopumilus maritimus
E)   Sulfolobus solfataricus

Question 17

How do the Bacteria and Archaea differ in the way the flagellum proteins are handled?

Accepted Answer

A)   Archaea proteins are assembled inside the cell for transport out of the cell.
B)   Archaea proteins are excreted to the outside of the cell for self-assembly.
C)   Archaea proteins are added to the growing flagellum shaft at the base.
D)   Archaea proteins are transported through the hollow flagellum tube for assembly at the end of the flagellum.
E)   Archaea proteins are enclosed within a membrane and moved to the outside of the cell.

Question 18

What is the size range of a typical Archaea cell?

Accepted Answer

A)  1 - 5 nm
B)   20 - 50 nm
C)   1 - 5 µm
D)   20 - 50 µm
E)   1 - 5 mm

Question 19

In which of these are Archaea and Bacteria significantly different?

Accepted Answer

A)   cell size
B)   chromosome size and organization
C)   lack of a membrane-enclosed nucleus
D)   membrane lipid structure
E)   possessesion of membrane enclosed organelles

Question 20

Which of these is one of the main functions of the cytoplasmic membrane in Archaea?

Accepted Answer

A)   It protects against effects of differing osmotic pressure
B)   It gives the cell its characteristic shapes
C)   It acts as a semi permeable barrier to the diffusion of molecules into and out of the cell.
D)   It prevents the diffusion of gases into and out of the cell.
E)   It allows attachment to specific receptor molecules on solid surfaces in the environment.

Exam 4: Archaea

All known methanogens are found in the domain ___.

From which area would you be able to isolate the bacterium Halobacterium?

You would be able to find methanogens in all of the following environments EXCEPT:

Why did Woese and Fox use rRNA gene sequences to compare the phylogenetic relatedness between microbes?

The secondary structure and amino acid composition of proteins from hyperthermophiles differ somewhat from proteins in mesophiles.What would you expect to find in thermophiles?

What is the specific action of bacteriorhodopsin?

What are chaperonins ("molecular chaperones") ?

Some archaeal cells contain pseudopeptidoglycan as their major cell wall component.What is this material composed of?

All members of the Archaea live in extreme environments.

Why might the process of chemotaxis in the archaeon Halobacterium be similar to chemotaxis in Bacteria?

Besides the methanogens and the halophiles,the phylum Euryarchaeota contains many thermophiles and hyperthermophiles.Most of these are also classified as _____ .

Members of the archaeal phylum Euryarchaeota are similar in their rRNA gene sequence but differ greatly in their metabolic characteristics.

Evidence clearly shows that Archaea are direct descendants of the earliest life forms.

How does the Archaea cytoplasmic membrane differ- from the Bacteria membrane?

Many cultured and characterized strains from the phylum Crenarchaeota were isolated from _____ .

Which member of the Archaea domain is a parasite of the archaeon Ignicoccus hospitalis and has one of the smallest genomes of all living microbes?

How do the Bacteria and Archaea differ in the way the flagellum proteins are handled?

What is the size range of a typical Archaea cell?

In which of these are Archaea and Bacteria significantly different?

Which of these is one of the main functions of the cytoplasmic membrane in Archaea?