Microbiology quiz 1 Flashcards

1. The scientist usually considered the first to see microorganisms, which he called "animalcules", was

A.

Redi.

B.

van Leeuwenhoek.

C.

Pasteur.

D.

Tyndall.

2. The word "animalcule" was coined by

A. Pasteur.
B. van Leeuwenhoek.
C. Redi.
D. Tyndall.

The idea of spontaneous Generation postulated that

A. organisms could evolve into the next generation of organisms.
B. organisms could spontaneously combust.
C. organisms could spontaneously arise from other living organisms.
D. living organisms could spontaneously arise from non-living material.

4. Which of these scientist(s) was/were involved in, among other things, investigating the idea of spontaneous generation?
A. Redi
B. van Leeuwenhoek
C. Pasteur
D. Escherich
E. Redi AND Pasteur

5. The work of Tyndall and Cohn
A. supported the idea of spontaneous generation.
B. was used to explain why others investigating spontaneous generation had obtained results that were opposite of those obtained by Pasteur.
C. showed that microbes caused disease.
D. allowed scientists to see microorganisms.

The structures present in the hay infusions used in experiments on spontaneous generation that made them difficult to sterilize are

A. chlorophyll.
B. toxins.
C. organelles.
D. endospores.

7. The opposite results obtained by scientists apparently doing the same experiments in investigating spontaneous generation
A. shows the importance of repeating experiments.
B. shows the importance of exactly duplicating experimental conditions.
C. led to further experiments that ultimately furthered knowledge.
D. All of the choices are correct.

If while investigating spontaneous generation, Pasteur had his laboratory located in a stable

A. the results would, most likely, have supported the idea of spontaneous generation.
B. the results would, most likely, have not supported the idea of spontaneous generation.
C. this would have had no effect on his results.
D. this would have shown his love of horses.

9. Cellulose is a major component of plants and is only directly digested by
A. herbivores.
B. carnivores.
C. termites.
D. microorganisms.

10. Plants are dependent on microorganisms for
A. providing oxygen.
B. providing water.
C. changing atmospheric nitrogen to a usable form.
D. providing carbohydrates.

11. Microorganisms are involved in
A. causing disease.
B. curing/treating disease.
C. preparing food.
D. cleaning up pollutants.
E. All of the choices are correct.

12. Bacteria have been used to help produce or modify food products
A. for several thousand years.
B. since the Middle Ages.

C. since the late 1800s.

D. since the 1950s.

13. Microorganisms are involved in
A. production of medicinal products.
B. transforming atmospheric nitrogen to a form useful to plants.
C. food production.
D. pollution cleanup.
E. All of the choices are correct.

14. Bioremediation refers to
A. rehabilitating wayward bacteria.
B. using bacteria to clean up pollutants.
C. vaccine development.
D. monitoring newly discovered disease organisms.

15. The Golden Age of Medical Microbiology
A. occurred during the late 1800s to early 1900s.
B. started in the 1990s with the advent of genetic engineering.
C. is a time when the knowledge of and techniques to work with bacteria blossomed.
D. was when people realized that diseases could be caused by invisible agents.
E. occurred during the late 1800s to early 1900s, is a time when the knowledge of and techniques to work with bacteria blossomed AND was when people realized that diseases could be caused by invisible agents.

Newly emerging or reemerging diseases

A. may be due to changing lifestyles.
B. are exemplified by Lyme disease and toxic shock syndrome.

C. may reflect a breakdown in sanitation/social order.

D. may be related to global cooling.
E. may be due to changing lifestyles, are exemplified by Lyme disease and toxic shock syndrome, AND may reflect a breakdown in sanitation/social order.

Lyme disease is an example of a disease

A. that is due to a greater degree of interaction between humans and tick-carrying animals.
B. that is due to a decline in vaccinations.
C. that is due to a mutation in the human genome.
D. that is due to climate change leading to a greater mosquito population.

18. The outbreak of measles within the last few years was due to
A. mutation of the virus.
B. change in the environment.
C. a decline in vaccination of children in the previous years.
D. increase in sensitivity of detection techniques.

19. Smallpox
A. has been eliminated as a naturally occurring infection in human beings.
B. still occasionally occurs in third world countries.

C. probably only had a human reservoir.
D. was dealt with by vaccination.
E. has been eliminated as a naturally occurring infection in human beings, AND was dealt with by vaccination.

20. Smallpox
A. aided European domination of new world nations.

B. has not occurred naturally anywhere in the world since 1977.
C. has potential as a weapon of bioterrorism.
D. has killed millions of people.
E. All of the choices are correct.

21. Diseases such as ulcers and cardiovascular disease
A. have been shown to be, or may be due to, a bacterial infection.
B. are solely due to lifestyle.
C. are solely due to genetics.
D. are due to new mutations in bacteria.

22. Bacteria are useful to study because
A. they produce protein in a similar manner to more complex organisms.
B. they replicate DNA in a similar manner to more complex organisms.
C. they produce energy in a similar manner to more complex organisms.
D. they are grown quickly, easily, and cheaply.
E. All of the choices are correct.

23. Bacteria
A. are not found on our bodies.
B. are only found on small select parts of our bodies.
C. provide protection to us from disease by covering our bodies, crowding out "bad" invading bacteria.

D. always cause disease when growing on our bodies.

24. Bacteria are present on the body
A. only during disease-causing infections.
B. constantly.
C. only in certain restricted areas.
D. never.

25. Bacteria are good models to use because they
A. are large in size.
B. share many biochemical/physiological properties with more complicated organisms.
C. can be assembled into multicellular organisms.
D. have complicated growth requirements.

Which is usually true of bacteria?

A. They are found as rods, spheres, or spirals.
B. They reproduce by binary fission.
C. They contain rigid cell walls made of peptidoglycan.
D. They are found as single cells.
E. All of the choices are correct.

Which is usually true of archaea?

A. They are found as rods, spheres, or spirals.
B. They reproduce by binary fission.
C. They contain rigid cell walls.
D. They are found as single cells.
E. All of the choices are correct.

Which is not usually true of archaea?

A. They are found as rods, spheres, or spirals.
B. They reproduce by binary fission.
C. They contain rigid cell walls.
D. They are found as single cells.
E. They contain peptidoglycan as part of their cell walls.

Some archaea are commonly found in

A. meteors.
B. boiling hot springs.
C. the Great Salt Lake.
D. your refrigerator.
E. boiling hot springs AND the Great Salt Lake.

The cell types that lack a membrane-bound nucleus are found in the

A. eukaryotes.
B. prokaryotes.
C. archaea.
D. protista.
E. prokaryotes AND archaea.

31. The prokaryotic cell scheme is found in
A. bacteria.

B. archaea.

C. eucarya.

D. All of the choices are correct.
E. bacteria AND archaea.

32. Eucarya
A. consist of only multicellular organisms.
B. have a more complex internal structure than archaea or bacteria.

C. have a simpler internal structure than archaea or bacteria.

D. have a membrane around the DNA.
E. have a more complex internal structure than archaea or bacteria AND have a membrane around the DNA.

33. Which group(s) below contain single-celled and multicellular organisms?
A. Algae

B. Fungi

C. Protozoa

D. All of the choices are correct.
E. Algae AND Fungi

34. Organisms
A. may be classified in four domains.
B. may be classified in three domains.
C. probably do not have a common ancestor.
D. have never shared genes between domains.

35. The system by which organisms are named is referred to as
A. systematics.
B. naming.
C. nomenclature.
D. cladistics.

36. The scientific name of an organism includes its
A. family and genus.
B. first name and last name.
C. genus and species.
D. domain.
E. genus and species AND domain.

37. Which is/are the correct form(s)?
A. Staphylococcus aureus
B. Staphylococcus aureus
C. staphylococcus aureus
D. S. aureus
E. Staphylococcus aureus AND S. aureus

38. Which of these may pertain to the term strain?
A. E. coli 0157:H7
B. E. coli
C. Minor variation of a species

D. Major variation of a species

E. E. coli 0157:H7 AND minor variation of a species

39. Viroids
A. are naked (lacking a protein shell) pieces of RNA.
B. are naked (lacking a protein shell) pieces of DNA.
C. are known to cause neurodegenerative diseases in animals.
D. are composed of protein encasing DNA.
E. are known to cause neurodegenerative diseases in animals AND are composed of protein encasing DNA.

40. Outside a cell, viruses are
A. running a small number of biochemical reactions.
B. synthesizing proteins necessary for entry into the host.
C. inactive.
D. constructing a cell membrane known as an envelope.
E. running a small number of biochemical reactions AND synthesizing proteins necessary for entry into the host.

41. Viruses may only be grown
A. in sterile, cell-free chemical growth media.
B. in living cells.
C. at body temperature.
D. in darkness.

42. Viruses are in the group
A. viridaeae.

B. eukarya.

C. archaea.

D. bacteria.

E. None of the choices is correct.

43. Viruses
A. are obligate intracellular parasites.
B. are single-celled organisms.
C. consist of only proteins.

44. Viruses are often referred to as
A. infectious agents.
B. eubacteria.
C. archaebacteria.
D. cellular agents.

45. Viruses, viroids, and prions all

A. operate intracellularly.
B. may be considered acellular agents of disease.
C. contain DNA.
D. infect only animals.
E. operate intracellularly AND may be considered acellular agents of disease.

46. Both viruses and viroids are
A. capable of independent reproduction.
B. obligate intracellular parasites.
C. interdependent with one another for reproduction.
D. larger than most bacteria in size.

47. Prions
A. are only composed of RNA.
B. are only composed of DNA.
C. are only composed of protein.
D. cause diseases in plants.
E. are only composed of RNA AND cause diseases in plants.

48. The smallest organism is probably determined by
A. the number of molecules necessary for its growth and replication.
B. the size of the molecules necessary for its growth and replication.
C. its membrane.
D. its volume.
E. the number of molecules necessary for its growth and replication AND the size of the molecules necessary for its growth and replication.

49. A new organism was found that was unicellular and 1 cm long. The "large" size of this organism alone would
A. mean that it could not be a bacterium.
B. mean that it had to be a protista.
C. mean little.

50. Although it is said that the twentieth century was the Age of Physics, it is predicted that the twenty-first century will be the age of
A. chemistry.
B. computers.
C. microbial biodiversity.
D. mathematics.

HIV/AIDS can be categorized as a new or emerging infectious disease. By putting it into this category, we are effectively saying that

A. this infection hasn't been observed in the human population prior to recent (approximately 50 years or sooner) outbreaks.
B. this disease has been in susceptible populations for centuries, but has only recently achieved infection levels that became detectable.
C. the infectious agent is still evolving and changing, unlike with older, more established diseases such as plague or polio.
D. the disease has always been in susceptible populations and causing disease, but we lacked the technology to detect it.

An illness outbreak occurs in New York City birds in the late 1990s. After a lengthy scientific investigation, the Centers for Disease Control (CDC) determine that the agent causing the birds to die is the West Nile virus. Outbreaks of this illness have been observed in several other countries in Asia and the Middle East across the last 50 years, but not in the United States. With this information, what would be the best categorization of this infectious agent/disease

A. This is clearly a reemerging infection. It's been around for a long time, and it is reappearing in a susceptible population again.

B. This is clearly a nosocomial infection. It's transmitted from animals to human beings in urban environments.

C. This is clearly an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population.
D. This is clearly not a concern to human beings--maybe it's emerging in animals, maybe it's reemerging, maybe it's nosomial. But who cares? It's only in birds.

64. Why are we concerned at all with monitoring emerging/reemerging diseases?
A. These represent growing threats to human health that will require new scientific research and resources to effectively combat.
B. Because globalization (greater trade and travel between countries) leads to more chances for spread of illnesses into new areas and populations. Monitoring these illnesses will help us to protect people.

C. Because the speed of travel has increased greatly. With increased speed of travel, it is far more likely that a serious pathogenic threat from one area of the world can spread rapidly across the globe in a very fast manner. We need to monitor the occurrence of these illnesses to try to protect populations.

D. All of the above.

A microbiologist obtained two pure isolated biological samples: one of a virus, and one of a viroid. The labels came off during a move from one lab to the next, however. The scientist felt she could distinguish between the two samples by analyzing for the presence of a single type of molecule. What type of molecule would she be looking for to differentiate between the two?

A. DNA
B. Protein

C. Lipids

D. RNA

1. Eukaryotic cells are
A. less complex than prokaryotic cells.
B. members of the Domains Bacteria and Archaea.

C. defined by the presence of a membrane bound nucleus.

D. able to reproduce more rapidly than prokaryotes.

2. The two magnifying lenses found in a light microscope are the
A. basic and transverse.
B. small and large.
C. ocular and objective.
D. simple and phase.

3. The resolving power of a microscope is described as the ability of the microscope to
A. separate clearly two objects that are very close together.
B. magnify an object.
C. separate the colors of an organism's internal structure.
D. see structures at various depths in a tissue.

4. In viewing a microscopic specimen, oil is used to
A. increase the refraction.
B. decrease the refraction.
C. increase the reflection.
D. increase the resolution.
E. decrease the refraction AND increase the resolution.

The use of oil with certain high-power objective lenses increases

A. magnification.
B. the amount of light that enters the objective lens.
C. resolution.
D. contrast.
E. resolution AND the amount of light that enters the objective lens.

6. If everything else is equal, the best way to observe more details in a microscopic specimen is to
A. increase resolution.
B. increase magnification.

7. The microscope that allows the specimen to appear three-dimensional is the

A. phase contrast microscope.

B. interference microscope.

C. fluorescence microscope.
D. dark-field microscope.

8. Which of the following microscope types would be least useful in viewing unstained living cells?
A.

Phase contrast

B.

Interference

C.

Bright-field

D.

Dark-field

9. Electron microscopes differ from light microscopes in that
A. electrons replace light.
B. electromagnets replace glass lenses.
C. resolution is higher.
D. magnification is higher.
E. All of the choices are correct.

10. Specimens can be observed at the atomic level using a(n)
A. scanning electron microscope.
B. transmission electron microscope.
C. atomic force microscope.
D. All of the choices are correct.
E. None of the choices is correct.

11. An electron microscope must use electromagnet "lenses" shaped like donuts to direct the electrons onto the specimen. Why?

A. Electrons are particles-there are also particles in air. Without a vacuum, the electrons would strike and be scattered by the atoms/particles within the air.
B. Because electrons are highly radioactive, and the chamber must be completely sealed to prevent them from escaping and contaminating the lab area.
C. This is the method for fixing the specimen to the slide grid for an electron microscope. Without fixing the specimen by vacuum, it would slide off and we wouldn't be able to visualize it.
D. All of the above are true.

12. An electron microscope must use electromagnet 'lenses'shaped like donuts to direct the electrons onto the specimen. Why aren't they solid, like the lenses in a light microscope?
A. A magnetic field cannot be applied across a completely solid object-there must be an opening within the object for the field to be applied through.
B. The user has to be able to physically look through the magnets to focus the beam of electrons onto the specimen, since the metal of the magnets is opaque. Without a hole in the middle, the user wouldn't be able to see!
C. The electrons would destroy the electromagnet material unless there was a physical hole for them to travel through on their way to the specimen.
D. Electrons are particles, and particles cannot travel through a solid item. The hole in the middle allows them to travel from the source of the electrons to the specimen.

13. Which microscope would be the BEST selection for examination of a virus?
A. Confocal scanning laser microscope
B. Atomic force microscope
C. Dark-field light microscope
D. Scanning electron microscope

14. Individual atoms on the surface of prepared samples can be observed by using the
A. phase contrast microscope.
B. scanning electron microscope.
C. dark-field microscope.
D. atomic force microscope.

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

16. Which of the following stains is/are considered differential?
A. Capsule stain.

B. Flagella stain.

C. Acid-fast stain.

D. Gram stain.

E. Acid-fast stain AND Gram stain.

17. The Gram stain and the endospore stain both use
A.

crystal violet.

B.

iodine.

C. safranin.
D. malachite green.

E.

acidic dyes.

18. The order of reagents in the Gram stain reaction are
A. safranin, alcohol, methylene blue, iodine.
B. crystal violet, iodine, alcohol, safranin.
C. methylene blue, alcohol, safranin.
D. crystal violet, alcohol, iodine, safranin.

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

Decolorizing too long

B.

Decolorizing too short

C.

Using old cultures

D.

Using young cultures

E. Decolorizing too long AND using old cultures

20. The major criteria used in placing bacteria into different groups is based on differences in
A. cell wall structure.
B. cell membrane permeability.
C. presence or absence of flagella.
D. detergent susceptibility.

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

Fix, smear, stain

B. Smear, fix, stain

C.

Fix, stain, decolorize

D.

Smear, decolorize, stain

22. The acid-fast stain
A. reflects differences in cytoplasmic membrane structure.
B. is useful for distinguishing a small group of organisms, including Mycobacterium.
C. uses crystal violet and safranin.
D. uses carbolfuchsin and methylene blue.
E. is useful for distinguishing a small group of organisms, including Mycobacterium AND uses carbolfuchsin and methylene blue.

23. Capsules
A. take up stain well.
B. may correlate with an organism's ability to cause disease.
C. are typically "negatively" stained.
D. are stained as a wet mount.
E. may correlate with an organism's ability to cause disease, are typically "negatively" stained, AND are stained as a wet mount

24. The endospore stain
A. is applicable to only a few groups of bacteria.
B. usually shows the spores as green structures among a background of pink cells.
C. uses crystal violet as the primary stain.
D. is an example of a negative stain.
E. is applicable to only a few groups of bacteria AND usually shows the spores as green structures among a background of pink cells.

25. Immunofluorescence
A. uses fluorescently tagged molecules.
B. makes use of the specificity in binding of antibodies.
C. utilizes acridine orange.
D. would require a special UV microscope.
E. uses fluorescently tagged molecules, makes use of the specificity in binding of antibodies, AND would require a special UV microscope.

26. Which term(s) refer(s) to bacterial morphology?
A. Bacillus
B.

Coccus

C.

Polyhedral

D.

Coccus AND Bacillus

27. Which is not true of the cytoplasmic membrane?
A. It defines the boundaries of the cell.
B. It is a semipermeable barrier.
C. It consists mainly of a fixed, static, phospholipid bilayer.

D. It uses proteins as selective gates and sensors.

E. All of the choices are true.

28. Which is true of simple diffusion of water?
A. Water usually enters a cell and produces a tremendous osmotic pressure.
B. Water usually leaves the cell and produces negative osmotic pressure.
C. Water tends to enter and leave the cell equally, resulting in no pressure in the cell.
D. The diffusion ultimately relies on the selectively permeable nature of the cell membrane.
E. Water usually enters a cell and produces a tremendous osmotic pressure AND the diffusion ultimately relies on the selectively permeable nature of the cell membrane.

29. The cytoplasmic membrane of both eukaryotes and prokaryotes functions to
A. form endoplasmic reticulum.
B. produce energy.
C. regulate movement of molecules that enter and leave the cell.

D. form lysosomes and Golgi apparatus.

The proteins of bacteria that are involved in the movement of small molecules into the cell are called

A. transport proteins.
B. permeases.
C. carriers.
D. peptidases.
E. transport proteins, permeases, AND carriers.

31. Most solutes pass through the cytoplasmic membrane via
A. osmosis.
B. diffusion.
C. transport proteins.
D. secretion.

32. Facilitated diffusion and active transport
A. both transport molecules into or out of a cell.
B. are both not very specific as to which molecules are transported.
C. both require a concentration gradient to function.
D. both require an expenditure of energy in order to transport the molecules.
E. both require a concentration gradient to functi

33. The macromolecule found in the cell walls of all bacteria is
A. lipid A.

B. teichoic acid.
C. peptidoglycan.
D. glycocalyx.

Which is (are) true concerning the cell wall of prokaryotes?

A. It determines the shape of the bacteria.
B. It prevents the bacteria from bursting.
C. It contains peptidoglycan.
D. It may be targeted by antimicrobials.
E. All of the choices are true.

35. Which amino acid(s) is/are found only in the cell walls of bacteria?
A.

Glycerol

B. L-form of glycine
C. Diaminopimelic acid

D. L-form of methionine
E. L-form of glycine AND L-form of methionine

36. The cell wall of Gram-positive bacteria
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.

37. Which molecules are associated with the cell wall of Gram-positive bacteria?
A. Peptidoglycan

B. D-form amino acids
C. Teichoic acids

D. LPS
E. Peptidoglycan, D-form amino acids, AND teichoic acids

38. The cell wall of Gram-negative organisms
A. has a thick peptidoglycan layer.
B. has a thin peptidoglycan layer.
C. is more permeable to various molecules than the Gram-positive cell wall.
D. is characterized by an outer membrane containing LPS.
E. has a thin peptidoglycan layer AND is characterized by an outer membrane containing LPS.

39. Endotoxin
A. consists of LPS.
B. determines bacterial shape.
C. may have different effects depending on the specific bacterial source.
D. is toxic due to the effects of the peptide side chains.
E.

40. Penicillin would be most effective against
A. non-growing bacteria.
B. growing bacteria.
C. Gram-positive bacteria.
D. Gram-negative bacteria.
E. growing bacteria AND Gram-positive bacteria.

41. Peptidoglycan
A. may be digested by penicillin.
B. consists of a long string of NAG coupled to a long string of NAM.
C. may be digested by lysozyme.
D. is found in bacteria, archaea, and plants.

42. Which of the following bacteria lack a cell wall?
A. Treponema pallidum
B. Mycobacterium tuberculosis
C. Staphylococcus aureus
D. Mycoplasma pneumoniae

43. The capsule
A. may be used for protection.
B. may be used to help the bacteria adhere to surfaces.
C. may be involved in movement.
D. may be involved in energy production.
E. may be used for protection AND may be used to help the bacteria adhere to surfaces.

44. The structures used for motility in both eukaryotes and prokaryotes are
A. cilia.
B. flagella.
C. pili.
D. fimbriae.

45. Movement in bacteria
A. is directly to or away from a stimulus.
B. relies on the beating of cilia.
C. is often referred to as run and tumble.
D. may involve pili.
E. is often referred to as run and tumble AND may involve pili.

46. Extrachromasomal DNA is found in ____________________________.
A. mitochondria
B. plasmids
C. nucleoid
D. nucleoli
E. mitochondria AND plasmids

47. Endospores are
A. a dormant cell type.
B. a form of reproduction.
C. an obligate intracellular parasite.
D. sensitive to damaging environmental conditions.

48. Eukaryotic cells
A. are more obviously compartmentalized than prokaryotes.
B. usually have a single circular supercoiled piece of DNA.
C. contain peptidoglycan in the cell wall.
D. have the same size ribosomes as prokaryotes.
E. usually have a single circular supercoiled piece of DNA AND contain peptidoglycan in the cell wall.

49. The membranes of eukaryotes and mycoplasma
A. contain peptidoglycan.
B. contain sterols for "strength."

C. contain ergosterol.
D. are fixed static structures.

50. Phagocytosis
A. is the ingestion of particles and may be performed by animal cells.
B. is the ingestion of particles and may be performed by bacteria.
C. is the secretion of proteins.
D. is the formation of a lysosome.
E. is the ingestion of particles and may be performed by bacteria AND is the formation of a lysosome.

51. The cytoskeleton
A. is a dynamic structure composed of microtubules, microfilaments, and intermediate filaments.

B. is a static structure that gives a rigid shape to the cell.
C. consists of flagella and cilia that are internalized.
D. is not necessary for movement or reproduction.

52. The nucleus
A. is a double membrane sac containing DNA and is found in eukaryotes.
B. is a single phospholipid membrane sac containing prokaryotic DNA.
C. is a smaller structure contained within the eukaryotic nucleolus.
D. cannot transport molecules to the cytoplasm due to the double membrane barrier.

53. Which is not true of mitochondria and chloroplasts?
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.

54. An advantage of the smaller size of prokaryotes, compared to eukaryotes, is
A. high surface area relative to low cell volume.
B. more rapid growth rates.
C. compartmentalization of cellular processes in membrane-bound organelles.
D. predators, parasites, and competitors constantly surround them.
E. high surface area relative to low cell volume AND more rapid growth rates.

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

66. Your instructor wants you to bring in an example of a biofilm to your lab. Which choice is the best selection for bringing in an intact biofilm for further study?
A. Disconnecting and bringing in the old, mildewed showerhead from the showers in your dorm

B. Scraping the mold off of the shower curtain in your dorm's bathroom into a paper cup using a butter knife

C. Using a toothpick to scrape plaque off of your teeth and smearing it onto a slide to bring in to lab

D. Wiping a sponge across a slimy boulder in a stream in a nearby park and bringing it in to lab