Question 1

The use of oil with certain high power objective lenses increases

Accepted Answer

A)  magnification. 
B)  the amount of light that enters the objective lens. 
C)  resolution. 
D)  contrast. 
E)  All of the choices are correct. 
A)  magnification. 
B)  the amount of light that enters the objective lens. 
C)  resolution. 
D)  contrast. 
E)  All of the choices are correct.

Question 2

The microscope which allows the specimen to appear 3-dimensional is the

Accepted Answer

A)  phase contrast microscope. 
B)  interference microscope. 
C)  fluorescence microscope. 
D)  dark-field microscope. 
A)  phase contrast microscope. 
B)  interference microscope. 
C)  fluorescence microscope. 
D)  dark-field microscope.

Question 3

A newly developed antibiotic drug shows promise by inhibiting prokaryotic 70S ribosomes in initial studies. However, when animal studies are begun, it's noted that it also inhibits growth of animal cells. Aren't prokaryotic ribosomes different from eukaryotic ribosomes? How can this be happening?

Accepted Answer

A)  Perhaps the ribosomes aren't as different as we thought, so a drug can affect and impair both of them. 
B)  While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of chloroplasts in animal cells. 
C)  While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of mitochondria in animal cells. 
D)  Perhaps the scientists accidently combined their cultures of animal and bacterial cells-this might indicate an impairment in growth in the culture. In reality, it's still just impairing the bacterial cells. 
A)  Perhaps the ribosomes aren't as different as we thought, so a drug can affect and impair both of them. 
B)  While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of chloroplasts in animal cells. 
C)  While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of mitochondria in animal cells. 
D)  Perhaps the scientists accidently combined their cultures of animal and bacterial cells-this might indicate an impairment in growth in the culture. In reality, it's still just impairing the bacterial cells.

Question 4

Individual atoms on the surface of prepared samples can be observed by using the

Accepted Answer

A)  phase contrast microscope. 
B)  scanning electron microscope. 
C)  dark-field microscope. 
D)  atomic force microscope. 
A)  phase contrast microscope. 
B)  scanning electron microscope. 
C)  dark-field microscope. 
D)  atomic force microscope.

Question 5

Cilia and flagella project from the cell and are not covered by cytoplasmic membrane.

Accepted Answer

A) True 
 B)False

Question 6

Basic dyes

Accepted Answer

A)  have negative charges. 
B)  have positive charges. 
C)  are electrically neutral. 
D)  contain both positively and negatively charged particles. 
A)  have negative charges. 
B)  have positive charges. 
C)  are electrically neutral. 
D)  contain both positively and negatively charged particles.

Question 7

A research laboratory is investigating environmental factors that would inhibit the growth of Archaea. One question they have is if adding the antibiotic penicillin would be effective in controlling their growth. What do you think the outcome would be if they tried this?

Accepted Answer

A)  The penicillin wouldn't affect the Archaea because it prevents crosslinking of peptidoglycan-Archaea don't have this compound in their cell walls. 
B)  The penicillin will inhibit cell wall formation in the Archaea, killing them. 
C)  The penicillin will slow down the growth of the Archaea by damaging the cell wall, but they will still be able to grow somewhat. 
D)  The penicillin will enhance the growth of the Archaea by providing a rich nutrient source. 
A)  The penicillin wouldn't affect the Archaea because it prevents crosslinking of peptidoglycan-Archaea don't have this compound in their cell walls. 
B)  The penicillin will inhibit cell wall formation in the Archaea, killing them. 
C)  The penicillin will slow down the growth of the Archaea by damaging the cell wall, but they will still be able to grow somewhat. 
D)  The penicillin will enhance the growth of the Archaea by providing a rich nutrient source.

Question 8

A new drug is developed that targets a nd binds to the lipid A portion of LPS from Gram-negative bacterial cells. This drug shows a high degree of activity and binding in a test tube setting against purified lipid A. Based on this information,

Accepted Answer

A)  we should fast track this drug and get it out to physicians immediately to help prevent toxic/septic shock in humans. 
B) we should do some animal testing with whole Gram-negative cells and the drug before we jump to any conclusions. 
C)  we should next proceed by moving to testing in a test tube using whole Gram-negative cells to see if it binds with the same strength. 
D)  we should abandon the drug entirely. Binding to lipid A won't kill the bacteria, so the drug is useless to develop further. It wouldn't help humans who have septic shock at all. 
A)  we should fast track this drug and get it out to physicians immediately to help prevent toxic/septic shock in humans. 
B) we should do some animal testing with whole Gram-negative cells and the drug before we jump to any conclusions. 
C)  we should next proceed by moving to testing in a test tube using whole Gram-negative cells to see if it binds with the same strength. 
D)  we should abandon the drug entirely. Binding to lipid A won't kill the bacteria, so the drug is useless to develop further. It wouldn't help humans who have septic shock at all.

Question 9

The structures used for motility in both eukaryotes and prokaryotes are

Accepted Answer

A)  cilia. 
B)  flagella. 
C)  pili. 
D)  fimbriae. 
A)  cilia. 
B)  flagella. 
C)  pili. 
D)  fimbriae.

Question 10

Which may result in Gram-positive bacteria appearing to be Gram-negative?

Accepted Answer

A)  decolorizing too long 
B)  decolorizing too short 
C)  using old cultures 
D)  using young cultures 
E)  decolorizing too long AND using old cultures 
A)  decolorizing too long 
B)  decolorizing too short 
C)  using old cultures 
D)  using young cultures 
E)  decolorizing too long AND using old cultures

Question 11

The order of reagents in the Gram stain reaction are

Accepted Answer

A)  safranin, alcohol, methylene blue, iodine. 
B)  crystal violet, iodine, alcohol, safranin. 
C)  methylene blue, alcohol, safranin. 
D)  crystal violet, alcohol, iodine, safranin. 
A)  safranin, alcohol, methylene blue, iodine. 
B)  crystal violet, iodine, alcohol, safranin. 
C)  methylene blue, alcohol, safranin. 
D)  crystal violet, alcohol, iodine, safranin.

Question 12

The cell wall of Gram-positive bacteria

Accepted Answer

A)  contains a thin layer of peptidoglycan. 
B)  contains a thick layer of peptidoglycan. 
C)  is, due to its thickness, an excellent barrier to most molecules. 
D)  contains an outer membrane containing LPS. 
E)  contains a thin layer of peptidoglycan AND contains an outer membrane containing LPS. 
A)  contains a thin layer of peptidoglycan. 
B)  contains a thick layer of peptidoglycan. 
C)  is, due to its thickness, an excellent barrier to most molecules. 
D)  contains an outer membrane containing LPS. 
E)  contains a thin layer of peptidoglycan AND contains an outer membrane containing LPS.

Question 13

Extrachromasomal DNA is found in ____________________________.

Accepted Answer

A)  mitochondria 
B)  plasmids 
C)  nucleoid 
D)  nucleoli 
E)  mitochondria AND plasmids 
A)  mitochondria 
B)  plasmids 
C)  nucleoid 
D)  nucleoli 
E)  mitochondria AND plasmids

Question 14

You want to examine the structure of the protein coat of a virus by microscopy. Which microscope is your best choice, and why?

Accepted Answer

A)  The scanning electron microscope-it has excellent resolution and magnification, much higher than a light microscope, and can clearly visualize viruses. 
B)  An atomic force microscope-this has the highest resolution and magnification of the microscopes we discussed. Here, we want to visualize a subcomponent of the virus particles, so we need the best value for resolution and magnification we can possibly achieve. 
C)  A fluorescent microscope-this will let us tag the protein coat with colored dyes in order to visualize it using this light microscope at 1000x. 
D)  A bright-field light microscope-of course, we'll need to stain the viruses before we can visualize them against the bright white background at 1000x total magnification. 
A)  The scanning electron microscope-it has excellent resolution and magnification, much higher than a light microscope, and can clearly visualize viruses. 
B)  An atomic force microscope-this has the highest resolution and magnification of the microscopes we discussed. Here, we want to visualize a subcomponent of the virus particles, so we need the best value for resolution and magnification we can possibly achieve. 
C)  A fluorescent microscope-this will let us tag the protein coat with colored dyes in order to visualize it using this light microscope at 1000x. 
D)  A bright-field light microscope-of course, we'll need to stain the viruses before we can visualize them against the bright white background at 1000x total magnification.

Question 15

Endospores are involved in bacterial reproduction.

Accepted Answer

A) True 
 B)False

Question 16

Which is not true of mitochondria and chloroplasts?

Accepted Answer

A)  They are found in all organisms. 
B)  They contain DNA and 70S ribosomes. 
C)  They are capable of performing protein synthesis. 
D)  They generate ATP. 
A)  They are found in all organisms. 
B)  They contain DNA and 70S ribosomes. 
C)  They are capable of performing protein synthesis. 
D)  They generate ATP.

Question 17

Smooth endoplasmic reticulum is involved in protein synthesis.

Accepted Answer

A) True 
 B)False

Question 18

Penicillin affects the synthesis of phospholipids, thereby producing weak membranes and lysis of the bacteria.

Accepted Answer

A) True 
 B)False

Question 19

In a basic staining procedure, which is the correct order?

Accepted Answer

A)  fix, smear, stain 
B)  smear, fix, stain 
C)  fix, stain, decolorize 
D)  smear, decolorize, stain 
A)  fix, smear, stain 
B)  smear, fix, stain 
C)  fix, stain, decolorize 
D)  smear, decolorize, stain

Question 20

Mitochondria and chloroplasts are thought to have once been free living bacteria that invaded another cell.

Accepted Answer

A) True 
 B)False

Exam 3: Microscopy and Cell Structure

The use of oil with certain high power objective lenses increases

The microscope which allows the specimen to appear 3-dimensional is the

A newly developed antibiotic drug shows promise by inhibiting prokaryotic 70S ribosomes in initial studies. However, when animal studies are begun, it's noted that it also inhibits growth of animal cells. Aren't prokaryotic ribosomes different from eukaryotic ribosomes? How can this be happening?

Individual atoms on the surface of prepared samples can be observed by using the

Cilia and flagella project from the cell and are not covered by cytoplasmic membrane.

Basic dyes

A research laboratory is investigating environmental factors that would inhibit the growth of Archaea. One question they have is if adding the antibiotic penicillin would be effective in controlling their growth. What do you think the outcome would be if they tried this?

A new drug is developed that targets a nd binds to the lipid A portion of LPS from Gram-negative bacterial cells. This drug shows a high degree of activity and binding in a test tube setting against purified lipid A. Based on this information,

The structures used for motility in both eukaryotes and prokaryotes are

Which may result in Gram-positive bacteria appearing to be Gram-negative?

The order of reagents in the Gram stain reaction are

The cell wall of Gram-positive bacteria

Extrachromasomal DNA is found in ____________________________.

You want to examine the structure of the protein coat of a virus by microscopy. Which microscope is your best choice, and why?

Endospores are involved in bacterial reproduction.

Which is not true of mitochondria and chloroplasts?

Smooth endoplasmic reticulum is involved in protein synthesis.

Penicillin affects the synthesis of phospholipids, thereby producing weak membranes and lysis of the bacteria.

In a basic staining procedure, which is the correct order?

Mitochondria and chloroplasts are thought to have once been free living bacteria that invaded another cell.

Humans and the Microbial World

The Molecules of Life

Dynamics of Prokaryotic Growth

Control of Microbial Growth

Metabolism: Fueling Cell Growth

The Blueprint of Life, From Dna to Protein

Bacterial Genetics

Biotechnology and Recombinant Dna

Identification and Classification of Prokaryotes

The Diversity of Prokaryotic Organisms

The Eukaryotic Members of the Microbial World

Viruses, Viroids and Prions

The Innate Immune Response

The Adaptive Immune Response

Host-Microbe Interactions

Immunologic Disorders

Applications of Immune Responses

Epidemiology

Antimicrobial Medications

Respiratory System Infections

Skin Infections

Wound Infections

Digestive System Infections

Genitourinary Infections

Nervous System Infections

Blood and Lymphatic Infections

Hiv Disease and Complications of Immunodeficiency

Microbial Ecology

Environmental Microbiology: Treatment of Water, Wastes, and Polluted Habitats

Food Microbiology

Filters