Question 1

Explain how a genetic approach can be used to understand cell division. Give an example.

Accepted Answer

First, genetic mutants are obtained that

Question 2

Describe two mechanisms that archaea may use to enhance the heat stability of the membrane.

Accepted Answer

First of all, the archaea have ether lin

Question 3

Describe the Gram-negative cell envelope. Why are porins necessary in the outer membrane of Gram-negative cells?

Accepted Answer

Covering the cytoplasmic membrane is a t

Question 4

You study a bacterium that grows in very low-nutrient aqueous environments. Which type of transport mechanism is required to deliver nutrients from these environments where they are at a lower concentration than inside the cell?

Accepted Answer

A)  aquaporins 
B)  active transport 
C)  facilitated diffusion 
D)  passive diffusion 
E)  Such bacteria cannot exist. 
A)  aquaporins 
B)  active transport 
C)  facilitated diffusion 
D)  passive diffusion 
E)  Such bacteria cannot exist.

Question 5

All of the following are true about prokaryotic outer membranes EXCEPT that they

Accepted Answer

A)  are lipid bilayers composed of identical phospholipids. 
B)  are found only in Gram-negative bacteria. 
C)  contain endotoxin. 
D)  contain proteins involved in transport. 
E)  contain lipopolysaccharide. 
A)  are lipid bilayers composed of identical phospholipids. 
B)  are found only in Gram-negative bacteria. 
C)  contain endotoxin. 
D)  contain proteins involved in transport. 
E)  contain lipopolysaccharide.

Question 6

Which of the following is FALSE regarding the polarity and aging of Caulobacter crescentus?

Accepted Answer

A)  The protein TipN is involved. 
B)  The two poles of the cell are different. 
C)  It contributes to a life cycle. 
D)  It results in two cell types (i.e., stalked cell and swarmer). 
E)  It results in two cell types, each with a monotrichous flagellum. 
A)  The protein TipN is involved. 
B)  The two poles of the cell are different. 
C)  It contributes to a life cycle. 
D)  It results in two cell types (i.e., stalked cell and swarmer). 
E)  It results in two cell types, each with a monotrichous flagellum.

Question 7

Explain what happens when a cell comes into contact with water or ethanol. Why is 70% ethanol commonly used to treat wounds and surfaces?

Accepted Answer

Water can cross cell membranes by osmosi

Question 8

All of the following are true of supercoiling in chromosomal DNA EXCEPT that it

Accepted Answer

A)  doubles back and twists upon itself. 
B)  facilitates RNA transcription. 
C)  results in compaction. 
D)  is generated by gyrase. 
E)  is maintained by DNA-binding proteins. 
A)  doubles back and twists upon itself. 
B)  facilitates RNA transcription. 
C)  results in compaction. 
D)  is generated by gyrase. 
E)  is maintained by DNA-binding proteins.

Question 9

The z-ring is

Accepted Answer

A)  made up of an actin-like polymer. 
B)  involved in segregation of two to four nucleoids. 
C)  controlled by a nutrient-dependent regulator. 
D)  involved in replication but not cytokinesis. 
E)  involved in preventing transcription of noncoding regions of DNA. 
A)  made up of an actin-like polymer. 
B)  involved in segregation of two to four nucleoids. 
C)  controlled by a nutrient-dependent regulator. 
D)  involved in replication but not cytokinesis. 
E)  involved in preventing transcription of noncoding regions of DNA.

Question 10

Efflux pumps send antibiotics, such as the protein synthesis-inhibitor tetracycline, out of the bacterial cells, enabling them to grow in the presence of antibiotics. Which of the following therapeutic approaches will be LEAST effective?

Accepted Answer

A)  Switch to an antibiotic that is not a substrate of the efflux pump. 
B)  Augment the treatment with an efflux inhibitor. 
C)  Increase the concentration of tetracycline. 
D)  Augment the treatment with an ATP synthase inhibitor. 
E)  Add a second antibiotic to the therapy. 
A)  Switch to an antibiotic that is not a substrate of the efflux pump. 
B)  Augment the treatment with an efflux inhibitor. 
C)  Increase the concentration of tetracycline. 
D)  Augment the treatment with an ATP synthase inhibitor. 
E)  Add a second antibiotic to the therapy.

Question 11

Which age class of M. tuberculosis (age 1 or age 3) do you think would be more resistant to quinolones, which block gyrase that supercoils DNA?

Accepted Answer

The polar-aging phenomenon of M. tubercu

Question 12

As proteins are found in various subcellular fractions, how could they be further analyzed?

Accepted Answer

A proteomic approach to knowing about th

Question 13

The ________ is the region between the cytoplasmic membrane and the outer membrane in Gram-negative cells.

Accepted Answer

A)  periplasm 
B)  cytoplasm 
C)  lysozyme 
D)  lipopolysaccharide 
E)  S-layer 
A)  periplasm 
B)  cytoplasm 
C)  lysozyme 
D)  lipopolysaccharide 
E)  S-layer

Question 14

You are studying life-forms in extreme environments, and you have discovered a microorganism with cardiolipin, hopanoids, and ester linkages in the membrane. It also has teichoic acids, galactans, and phenolic glycolipids in the cell wall. In addition, it is a porin similar to OmpA. This microorganism is most likely related to

Accepted Answer

A)  eukaryotic cells. 
B)  archaea. 
C)  mycobacteria. 
D)  Gram-positive bacteria. 
E)  Gram-negative bacteria. 
A)  eukaryotic cells. 
B)  archaea. 
C)  mycobacteria. 
D)  Gram-positive bacteria. 
E)  Gram-negative bacteria.

Question 15

In order for septation to occur, which process must finish first?

Accepted Answer

A)  transcription and translation 
B)  membrane synthesis 
C)  DNA replication 
D)  cell wall synthesis 
E)  synthesis of mreB 
A)  transcription and translation 
B)  membrane synthesis 
C)  DNA replication 
D)  cell wall synthesis 
E)  synthesis of mreB

Question 16

Which of the following is described as an attachment organelle that is a membrane-bound extension of the cytoplasm?

Accepted Answer

A)  pili 
B)  fimbriae 
C)  sex pili 
D)  stalks 
E)  flagella 
A)  pili 
B)  fimbriae 
C)  sex pili 
D)  stalks 
E)  flagella

Question 17

Lipopolysaccharides are found in

Accepted Answer

A)  all bacteria. 
B)  Gram-positive bacteria. 
C)  Gram-negative bacteria. 
D)  archaea. 
E)  eukaryotes. 
A)  all bacteria. 
B)  Gram-positive bacteria. 
C)  Gram-negative bacteria. 
D)  archaea. 
E)  eukaryotes.

Question 18

Extreme thermophiles have ________ chains in their membrane in order to maintain membrane stability.

Accepted Answer

A)  lipoprotein 
B)  hopanoid 
C)  cholesterol 
D)  terpenoid 
E)  cardiolipin 
A)  lipoprotein 
B)  hopanoid 
C)  cholesterol 
D)  terpenoid 
E)  cardiolipin

Question 19

All of the following are used by prokaryotic cells for attaching to solid surfaces EXCEPT

Accepted Answer

A)  endospore. 
B)  capsule. 
C)  stalks. 
D)  fimbriae. 
E)  pili. 
A)  endospore. 
B)  capsule. 
C)  stalks. 
D)  fimbriae. 
E)  pili.

Question 20

All of the following are true for DNA-binding proteins EXCEPT that they

Accepted Answer

A)  can form protective crystalline structures around organized DNA. 
B)  condense prokaryotic DNA. 
C)  can act as regulators of gene expression. 
D)  determine the shape of the cell. 
E)  help to keep cells viable for a longer duration of time. 
A)  can form protective crystalline structures around organized DNA. 
B)  condense prokaryotic DNA. 
C)  can act as regulators of gene expression. 
D)  determine the shape of the cell. 
E)  help to keep cells viable for a longer duration of time.

Exam 3: Cell Structure and Function

Explain how a genetic approach can be used to understand cell division. Give an example.

Describe two mechanisms that archaea may use to enhance the heat stability of the membrane.

Describe the Gram-negative cell envelope. Why are porins necessary in the outer membrane of Gram-negative cells?

You study a bacterium that grows in very low-nutrient aqueous environments. Which type of transport mechanism is required to deliver nutrients from these environments where they are at a lower concentration than inside the cell?

All of the following are true about prokaryotic outer membranes EXCEPT that they

Which of the following is FALSE regarding the polarity and aging of Caulobacter crescentus?

Explain what happens when a cell comes into contact with water or ethanol. Why is 70% ethanol commonly used to treat wounds and surfaces?

All of the following are true of supercoiling in chromosomal DNA EXCEPT that it

The z-ring is

Efflux pumps send antibiotics, such as the protein synthesis-inhibitor tetracycline, out of the bacterial cells, enabling them to grow in the presence of antibiotics. Which of the following therapeutic approaches will be LEAST effective?

Which age class of M. tuberculosis (age 1 or age 3) do you think would be more resistant to quinolones, which block gyrase that supercoils DNA?

As proteins are found in various subcellular fractions, how could they be further analyzed?

The ________ is the region between the cytoplasmic membrane and the outer membrane in Gram-negative cells.

In order for septation to occur, which process must finish first?

Which of the following is described as an attachment organelle that is a membrane-bound extension of the cytoplasm?

Lipopolysaccharides are found in

Extreme thermophiles have ________ chains in their membrane in order to maintain membrane stability.

All of the following are used by prokaryotic cells for attaching to solid surfaces EXCEPT

All of the following are true for DNA-binding proteins EXCEPT that they

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

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