Question 1

The bacterial cell wall of mycobacteria is highly hydrophobic due to presence of

Accepted Answer

A)  lipoproteins. 
B)  phenolic glycolipids. 
C)  phospholipids. 
D)  polysaccharides. 
E)  glycoproteins. 
A)  lipoproteins. 
B)  phenolic glycolipids. 
C)  phospholipids. 
D)  polysaccharides. 
E)  glycoproteins. B

Question 2

Mary Jane Osborn discovered that inner and outer membranes are different in density by using

Accepted Answer

A)  genetic analysis. 
B)  X-ray crystallography. 
C)  ultracentrifugation. 
D)  protein synthesis. 
E)  fluorescent. 
A)  genetic analysis. 
B)  X-ray crystallography. 
C)  ultracentrifugation. 
D)  protein synthesis. 
E)  fluorescent. C

Question 3

Explain the movement of a bacterium possessing flagella away from a toxic chemical.

Accepted Answer

Counterclockwise spinning of the flagella causes the cell to swim a long distance in one direction. Clockwise spinning causes the cell to tumble randomly. These motions are used together to result in a biased random walk that moves the cell in the overall direction away from the toxic chemical.

Question 4

E. coli and Sinorhizobium cell-surface proteins enable colonization of ________ and ________, respectively.

Accepted Answer

A)  the human intestinal epithelium; animal skin 
B)  legume plants; the human intestinal epithelium 
C)  the human intestinal epithelium; legume plants 
D)  legume plants; animal skin 
E)  cantaloupe; spinach 
A)  the human intestinal epithelium; animal skin 
B)  legume plants; the human intestinal epithelium 
C)  the human intestinal epithelium; legume plants 
D)  legume plants; animal skin 
E)  cantaloupe; spinach

Question 5

We cannot see the molecules within a cell, but ________ and ________ analysis generate a remarkably detailed view.

Accepted Answer

A)  structural; genetic 
B)  microscopy; genetic 
C)  chemical; subcellular 
D)  microscopy; subcellular 
E)  chemical; genetic 
A)  structural; genetic 
B)  microscopy; genetic 
C)  chemical; subcellular 
D)  microscopy; subcellular 
E)  chemical; genetic

Question 6

Some bacterial cells are inedible for humans because of the

Accepted Answer

A)  high ion content in the cytoplasm. 
B)  high proportion of nucleic acids that humans degrade to the waste product uric acid. 
C)  peptide-linked sugars in the cell wall cannot be digested. 
D)  high uric acid content of the cytoplasm. 
E)  high polyamine content, which is toxic. 
A)  high ion content in the cytoplasm. 
B)  high proportion of nucleic acids that humans degrade to the waste product uric acid. 
C)  peptide-linked sugars in the cell wall cannot be digested. 
D)  high uric acid content of the cytoplasm. 
E)  high polyamine content, which is toxic.

Question 7

How can weak acids and weak bases cause pH stress to cells?

Accepted Answer

A)  Only weak acids can cause stress by diffusing across a membrane at low pH. 
B)  Weak acids and weak bases do not cause stress. 
C)  If a cell has transporters that are not well regulated, weak acids or weak bases can accumulate inside the cells and cause stress. 
D)  At certain pHs, both weak acids or weak bases will be uncharged and thus are small uncharged molecules that can diffuse across a membrane and cause pH stress inside the cell. 
E)  Weak bases will only cause pH stress at low pH. 
A)  Only weak acids can cause stress by diffusing across a membrane at low pH. 
B)  Weak acids and weak bases do not cause stress. 
C)  If a cell has transporters that are not well regulated, weak acids or weak bases can accumulate inside the cells and cause stress. 
D)  At certain pHs, both weak acids or weak bases will be uncharged and thus are small uncharged molecules that can diffuse across a membrane and cause pH stress inside the cell. 
E)  Weak bases will only cause pH stress at low pH.

Question 8

Describe how vancomycin affects the cell wall of Gram-positive bacteria. How have some cells developed resistance?

Accepted Answer

Gram-positive bacteria have a D-ala- D-a

Question 9

Water can move across a membrane via passive diffusion but that movement is aided by

Accepted Answer

A)  aquaporins. 
B)  ion transporters. 
C)  active transport. 
D)  ethanol2. 
E)  weak acids and bases. 
A)  aquaporins. 
B)  ion transporters. 
C)  active transport. 
D)  ethanol2. 
E)  weak acids and bases.

Question 10

A medically important example of active transport is that of drug ________ proteins powered by the hydrogen ion gradient.

Accepted Answer

A)  efflux 
B)  porin 
C)  membrane-permeant 
D)  diffusion 
E)  lysis 
A)  efflux 
B)  porin 
C)  membrane-permeant 
D)  diffusion 
E)  lysis

Question 11

Directed movements toward or away from a chemical or physical signal are known as

Accepted Answer

A)  gliding. 
B)  flagellation. 
C)  chemotaxis. 
D)  locomotion. 
E)  slime layer. 
A)  gliding. 
B)  flagellation. 
C)  chemotaxis. 
D)  locomotion. 
E)  slime layer.

Question 12

Explain how any two specialized structures are involved in bacterial photosynthesis.

Accepted Answer

Thylakoids are structures of extensively

Question 13

All of the following are components of peptidoglycan EXCEPT

Accepted Answer

A)  N-acetylglucosamine. 
B)  N-acetylmuramic acid. 
C)  lipopolysaccharide. 
D)  amino acids. 
E)  peptide cross-links. 
A)  N-acetylglucosamine. 
B)  N-acetylmuramic acid. 
C)  lipopolysaccharide. 
D)  amino acids. 
E)  peptide cross-links.

Question 14

The proteins embedded in a membrane require that region to be

Accepted Answer

A)  crystalline. 
B)  hydrophobic. 
C)  flexible. 
D)  negatively charged. 
E)  positively charged. 
A)  crystalline. 
B)  hydrophobic. 
C)  flexible. 
D)  negatively charged. 
E)  positively charged.

Question 15

Describe any two roles for membrane proteins.

Accepted Answer

Answers can include any of the following

Question 16

Cell wall growth patterns of a variety of bacteria have been studied using fluorescently labeled D-amino acids. This approach has worked because

Accepted Answer

A)  fluorescent amino acids block further cell wall synthesis and thus provide a snapshot of the cell wall at a particular time. 
B)  ribosomes cannot incorporate any fluorescence and thus cannot use fluorescent amino acids; it all goes to cell wall. 
C)  vancomycin can block the incorporation of D-alanine into protein and thus force it into the cell wall. 
D)  the labeled amino acids are D-amino acids, not L-amino acids.; thus, they only were incorporated into cell wall. 
E)  This approach has not worked. 
A)  fluorescent amino acids block further cell wall synthesis and thus provide a snapshot of the cell wall at a particular time. 
B)  ribosomes cannot incorporate any fluorescence and thus cannot use fluorescent amino acids; it all goes to cell wall. 
C)  vancomycin can block the incorporation of D-alanine into protein and thus force it into the cell wall. 
D)  the labeled amino acids are D-amino acids, not L-amino acids.; thus, they only were incorporated into cell wall. 
E)  This approach has not worked.

Question 17

What unusual lipids are found in mycobacteria, and of what benefit are they to these bacteria?

Accepted Answer

Mycobacteria contain mycolic acids and p

Question 18

The molecule shown below is ________ and may play a role in ________.

Accepted Answer

A)  phosphatidylethanolamine; heat response 
B)  cardiolipin; heat response. 
C)  phosphatidylglycerol; heat response, 
D)  cardiolipin; starvation 
E)  phosphatidylglycerol; heat response,. 
A)  phosphatidylethanolamine; heat response 
B)  cardiolipin; heat response. 
C)  phosphatidylglycerol; heat response, 
D)  cardiolipin; starvation 
E)  phosphatidylglycerol; heat response,.

Question 19

The capsule polysaccharides form a slippery mucous layer that inhibits

Accepted Answer

A)  diffusion. 
B)  phagocytosis. 
C)  attachment. 
D)  lysis. 
E)  osmosis. 
A)  diffusion. 
B)  phagocytosis. 
C)  attachment. 
D)  lysis. 
E)  osmosis.

Question 20

Cells must be broken open in order to then fractionate the components. Each of the following can be used in bacterial cell breakage EXCEPT

Accepted Answer

A)  French press. 
B)  lysozyme . 
C)  mild detergent. 
D)  ultracentrifugation. 
E)  ultrasonic vibration. 
A)  French press. 
B)  lysozyme . 
C)  mild detergent. 
D)  ultracentrifugation. 
E)  ultrasonic vibration.

Exam 3: Cell Structure and Function

The bacterial cell wall of mycobacteria is highly hydrophobic due to presence of

Mary Jane Osborn discovered that inner and outer membranes are different in density by using

Explain the movement of a bacterium possessing flagella away from a toxic chemical.

E. coli and Sinorhizobium cell-surface proteins enable colonization of ________ and ________, respectively.

We cannot see the molecules within a cell, but ________ and ________ analysis generate a remarkably detailed view.

Some bacterial cells are inedible for humans because of the

How can weak acids and weak bases cause pH stress to cells?

Describe how vancomycin affects the cell wall of Gram-positive bacteria. How have some cells developed resistance?

Water can move across a membrane via passive diffusion but that movement is aided by

A medically important example of active transport is that of drug ________ proteins powered by the hydrogen ion gradient.

Directed movements toward or away from a chemical or physical signal are known as

Explain how any two specialized structures are involved in bacterial photosynthesis.

All of the following are components of peptidoglycan EXCEPT

The proteins embedded in a membrane require that region to be

Describe any two roles for membrane proteins.

Cell wall growth patterns of a variety of bacteria have been studied using fluorescently labeled D-amino acids. This approach has worked because

What unusual lipids are found in mycobacteria, and of what benefit are they to these bacteria?

The molecule shown below is ________ and may play a role in ________.

The capsule polysaccharides form a slippery mucous layer that inhibits

Cells must be broken open in order to then fractionate the components. Each of the following can be used in bacterial cell breakage EXCEPT

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

Filters

E. coli and Sinorhizobium cell-surface proteins enable colonization of and , respectively.

We cannot see the molecules within a cell, but and analysis generate a remarkably detailed view.

The molecule shown below is and may play a role in .