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Worksheets

FINAL

Total questions: 80

Worksheet time: 40mins

Name
Class
Date
1.

Endotoxin

a)

is toxic due to the effects of the peptide side chains.

b)

may have different effects depending on the bacterial species.

c)

consists of lipopolysaccharide.

d)

is found in Gram-positive cells.

e)

determines bacterial shape.

2.

Which of the following ways in which molecules move across a membrane does not require energy?

a)

Facilitated diffusion

b)

Group translocation

c)

ABC transporters

d)

Active transport

3.

What would be the total magnification of an image viewed on a bright-field microscope when using the ocular (10X) and the high power objective (40X)?

a)

1000X

b)

400X

c)

4000X

d)

10X

e)

40x

4.

Endospores are

a)

obligate intracellular parasites.

b)

a dormant cell type.

c)

made by all bacterial genera.

d)

involved in bacterial reproduction.

e)

sensitive to heat and dessication.

5.

The target of penicillin in bacterial cells is ______.

a)

70S ribosomes

b)

the DNA

c)

the cell membrane

d)

endospores

e)

the cell wall

6.

Which of the steps shown is found in the endospore and acid-fast stains but NOT in the simple stain or Gram stain?

a)

Alcohol decolorizer

b)

Making a bacterial smear

c)

Rinsing water

d)

Primary stain

e)

Heat during primary stain

7.

The simplest technique for isolating bacteria is referred to as the

a)

most probable number method.

b)

bacterial growth method.

c)

pour-plate method.

d)

serial dilution method.

e)

streak-plate method.

8.

In the Gram-positive bacterial cell wall, the polymers of NAM and NAG sugars in peptidoglycan are cross-linked together by tetrapeptide chains and ______.

a)

carbohydrate interbridges

b)

nucleic acid interbridges

c)

covalent interbridges

d)

fatty acid interbridges

e)

peptide interbridges

9.

Specimens can be observed at the atomic level using a(n)

a)

scanning electron microscope.

b)

transmission electron microscope.

c)

atomic force microscope.

d)

fluorescence microscope.

e)

light microscope.

10.

The idea of spontaneous generation postulated that

a)

living organisms could spontaneously arise from other living organisms.

b)

living organisms could spontaneously arise from non-living material.

c)

living organisms must contain at least ten cells.

d)

organisms could spontaneously turn into other types of organisms.

e)

organisms could evolve into the next generation of organisms.

11.

Bacteria are good research models because they

a)

vary in size from microscopic to macroscopic.

b)

develop the same diseases as humans and animals.

c)

share many properties with more complex organisms.

d)

have similarly complicated growth requirements.

12.

The solidifying agent used most successfully in bacterial nutrient media is

a)

peptone

b)

gelatin

c)

agar

d)

starch

e)

agarose

13.

The resolving power of a microscope is described as the ability of the microscope to

a)

separate the colors of an organism's internal structure.

b)

magnify structures at various depths in a tissue.

c)

separate clearly two objects that are very close together.

d)

combine the images of two objects that are very close together.

e)

magnify an object and its surroundings.

14.

You discover an encapsulated Gram-positive, peritrichous, spore-forming bacillus. Which of the following describes the organism?

a)

Spherical bacterium with a thin cell wall, a slime layer, and flagella distributed over its surface, that can form endospores for survival of adverse conditions.

b)

Rod-shaped bacterium with a thin cell wall, a capsule, and single flagellum at one end, that can form endospores for survival in adverse conditions.

c)

Rod-shaped bacterium with a thin cell wall, a slime layer, and single flagellum at one end, that can form endospores for survival in adverse conditions.

d)

Rod-shaped bacterium with a thick cell wall, a capsule, and flagella distributed over its surface, that can form endospores for survival of adverse conditions.

e)

Spherical bacterium with a thick cell wall, a slime layer, and a single flagellum at one side of the cell.

15.

Bacteria are present on the body

a)

at all times

b)

only after intense exercise.

c)

only in certain areas.

d)

only during disease-causing infections

e)

only after using public transport.

16.

Which of the statements about biofilms is TRUE? 

a)

Biofilms may protect organisms against harmful chemicals.

b)

Biofilms are very rarely involved in human bacterial infections.

c)

Biofilms are a peptidoglycan-encased community of microorganisms.

d)

Biofilms may significantly inhibit bioremediation efforts.

e)

Biofilms are very seldom found in a natural environment.

17.

All of the statements regarding archaea are true EXCEPT

a)

they contain peptidoglycan in their cell walls.

b)

they reproduce by binary fission.

c)

they are found as single cells

d)

they contain a rigid cell wall.

e)

they often grow in extreme environments.

18.

The movement of dissolved solutes from a region of higher concentration to a region of lower concentration is called _______.

a)

isotonic

b)

active transport

c)

diffusion

d)

osmosis

e)

hypotonic

19.

Bioremediation refers to

a)

development of new vaccines.

b)

monitoring newly discovered disease organisms.

c)

destroying organisms causing infectious diseases.

d)

using bacteria to clean up environmental pollutants.

e)

rehabilitating wayward pathogenic bacteria.

20.

The CORRECT order of reagent use in the Gram stain reaction is

a)

crystal violet, alcohol, iodine, safranin.

b)

safranin, alcohol, methylene blue, iodine.

c)

methylene blue, alcohol, safranin, iodine.

d)

crystal violet, iodine, alcohol, safranin.

e)

alcohol, safranin, iodine, crystal violet

21.

Ultraviolet radiation at the bactericidal wavelength destroys bacteria by

a)

disrupting ribosomes.

b)

destroying endospores.

c)

damaging nucleic acid.

d)

denaturing proteins.

e)

preventing spore formation.

22.

Hand washing with plain soap is very useful in controlling spread of microorganisms because

a)

plain soap is bacteriostatic and inhibits bacterial growth.

b)

it is very effective at the mechanical removal of microorganisms.

c)

all soaps are bacteriostatic and kill endospores.

d)

all soaps are virucidal and kill all viruses.

e)

plain soap is bactericidal and kills all bacteria.

23.

The term antiparallel

a)

refers to the sequence of nucleotides in DNA.

b)

refers to a type of prokaryotic replication.

c)

is synonymous with semiconservative.

d)

refers to the opposite orientation of the two strands in DNA.

e)

refers to the structure of single-stranded RNA.

24.

The 3' end of DNA

a)

usually has guanine and guanine attached to it.

b)

has a hydroxyl group attached to the number 3 carbon of deoxyribose.

c)

attaches to the 3' phosphate group of the incoming nucleotide.

d)

has a hydroxyl group attached to the number 3 carbon of ribose.

e)

always has thymine and uracil attached to it.

25.

GCCCAAAG is a molecule of

a)

RNA

b)

Protein

c)

DNA or lipid

d)

DNA

e)

Cannot tell as written

26.

If a 75 base-pair fragment of DNA has 25 cytosines in it, how many adenines would you expect it to have?

a)

100

b)

125

c)

25

d)

50

e)

70

27.

Microbial death rates may be affected by

a)

pH

b)

Temperature

c)

the presence of organics

d)

growth in a biofilm

e)

All of the answer choices are correct

28.

A sterile item is free of

a)

prions only.

b)

endospores, viruses, AND prions.

c)

microbes, endospores, AND prions.

d)

microbes, viruses, AND prions.

e)

all viable microbes, endospores, AND viruses.

29.

Which is true about prokaryotic (bacterial) RNA polymerase?

a)

It is used during transcription

b)

It requires a primer.

c)

It has a detachable subunit, alpha factor, which recognizes the promoter.

d)

It reads the template in the 5'-3' direction.

e)

All of the choices are true.

30.

One of the first chemicals used by Lister to prevent surgical infections was

a)

soap

b)

mercury

c)

alcohol

d)

carbolic acid

e)

iodine

31.

The E-site

a)

is the aminoacyl site on the ribosome.

b)

is responsible for the release of the tRNA.

c)

is another name for anticodon.

d)

is found on the RNA polymerase enzyme.

e)

is found on the 35S polysome.

32.

Without changing the sequence or the orientation of the sequence(s), which is/are complementary to the sequence 5' AGGCUAAC 3'?

a)

5' TCCGATTG 3'

b)

3' TCCGATTG 5'

c)

3' TCCGATTC 5' AND 5' CTTAGCCT 3'

d)

3' TAAGCTTA 5'

e)

5' CTTAGCCT 3'

33.

RNA is characterized by which one of the following features?

a)

thymine

b)

ribose

c)

all of the answer choices are correct

d)

double-stranded

e)

deoxyribose

34.

The most important function of nitrites in processed foods is to

a)

prevent browning of the product.

b)

destroy cell membranes of potential pathogens.

c)

inhibit the germination of Clostridium botulinum endospores.

d)

make the food more acidic.

e)

prevent carcinogen formation.

35.

There are ______ codons to code for the 20 possible amino acids.

a)

61

b)

30

c)

64

d)

20

e)

3

36.

Which of the following is NOT involved in transcription? 

a)

Uracil

b)

Ribosome

c)

Sigma factor

d)

Promotor

e)

Polymerase

37.

Which of the following is/are true of DNA replication?

a)

It starts at the origin of duplication.

b)

Nucleotides are added to the 3' end.

c)

It requires a DNA primer to get started.

d)

It is carried out by transcriptases.

e)

All of the choices are true.

38.

A stop codon

a)

codes for the stop amino acid AUG.

b)

codes for the stop amino acid s-methyl-methionine.

c)

codes for no amino acid.

d)

forms a hairpin loop forcing the ribosome to fall off.

e)

enhances the binding of the e-polymerase.

39.

Pasteurization

a)

is the use of heat to reduce numbers of pathogenic/spoilage bacteria in a food item to a safe level.

b)

is a mild heating process used to preserve only milk and milk products.

c)

is a process that uses short bursts of radiation to kill microorganisms on foods.

d)

is a process that uses intense cold to kill only pathogenic microorganisms on packaged foods.

e)

is the use of high moist heat to remove all bacteria and viruses from fresh food products for safety.

40.

The specific sequence of nucleotides in the DNA to which the RNA polymerase binds is the

a)

regulatory region.

b)

sigma region.

c)

core region.

d)

starter region

e)

promotor region

41.

Almost all of the antibodies found in a newborn are

a)

the result of active immunity.

b)

IgM.

c)

the result of passive immunity.

d)

the result of infection.

e)

self-made.

42.

The formation of a covalent bond between two adjacent thymines is caused by

a)

microwave radiation.

b)

UV radiation.

c)

heat.

d)

alkylating agents.

e)

X-rays.

43.

The F plasmid carries the information for

a)

the sex pilus.

b)

the Y chromosome.

c)

bacterial flagella.

d)

recipient cell DNA replication.

e)

antibiotic resistance.

44.

Attenuated agents are

a)

weakened but replicating microbes.

b)

toxins

c)

dead viruses.

d)

weakened, nonreplicating microbes.

e)

parts of an organism.

45.

Segments of DNA capable of moving from one area in the DNA to another are called

a)

inverted repeats

b)

mutagens.

c)

transposons.

d)

base analogs.

e)

intercalating agents.

46.

Which antibodies cross the placenta and protect the fetus?

a)

IgM

b)

IgM and IgG

c)

IgA

d)

IgG

e)

IgD

47.

What part of the attached bacteriophage enters through the host cell wall?

a)

The entire virus.

b)

Only the enzymes necessary for replication.

c)

The nucleic acid and capsid.

d)

The capsid only.

e)

The nucleic acid.

48.

The mechanism by which genes are transferred into bacteria via viruses is called

a)

conjugation.

b)

replica plating.

c)

transduction

d)

ellipsis.

e)

transformation.

49.

Fungal diseases are generally referred to as

a)

infestations.

b)

funguses.

c)

systemics.

d)

infections.

e)

mycoses.

50.

Irradiation of cells with ultraviolet light may cause

a)

adenine complementary base pairing with cytosine.

b)

cytosine trimers.

c)

thymine dimers.

d)

the addition of uracil.

e)

four nucleotides to covalently bind together.

51.

The source of variation among microorganisms that were once identical is

a)

mutant.

b)

antibiotic resistance.

c)

virulence factors.

d)

mutation.

e)

sigma factors.

52.

Outside of living cells, viruses are

a)

replicating by binary fission.

b)

metabolically inert.

c)

gaining ATP from the mitochondria.

d)

using cilia to move to the next host.

e)

scavenging glucose.

53.

Herd immunity

a)

occurs in a population in which a large percentage of the population is immune.

b)

only provides protection to those that are already immune.

c)

occurs in a population in which a large percentage of the population is immune AND is responsible for dramatic increases in childhood diseases.

d)

is responsible for dramatic increases in childhood diseases.

e)

only occurs in a population in which all individuals are immune.

54.

All of the following are true about attenuated agents EXCEPT

a)

they only induce immunity after several doses.

b)

they may cause disease in immunocompromised individuals.

c)

they multiply in the body.

d)

they may revert or mutate to disease-causing strains.

e)

they cause a strong cell-mediated immune response.

55.

Chemical mutagens that mimic the naturally occurring bases are called

a)

nucleobase copiers.

b)

nitrogen mustards.

c)

alkylating agents.

d)

base analogs.

e)

nitrous oxide.

56.

A tangle of fungal hyphae is generally known as a

a)

mycelium.

b)

spore.

c)

bud.

d)

germ tube.

e)

biofilm.

57.

The practice of deliberately stimulating the immune system is called

a)

memory immunity.

b)

vaccination.

c)

hypersensitivity.

d)

acquired immunity.

e)

autoimmunity.

58.

The causative agent of malaria is what type of microbe?

a)

Protozoan

b)

Mosquito

c)

Virus

d)

Fungus

e)

Bacterium

59.

The protein projections on the surface of a virus that are involved in attachment to the host cell are called

a)

hooks.

b)

spikes.

c)

suckers.

d)

cilia.

e)

pili.

60.

The symbiotic relationship wherein both partners benefit is termed

a)

parasitism.

b)

commensalism.

c)

dysbiosis.

d)

mutualism.

e)

independence.

61.

What part of the attached bacteriophage enters through the host cell wall?

a)

The capsid only.

b)

The nucleic acid and capsid.

c)

The nucleic acid.

d)

Only the enzymes necessary for replication.

e)

The entire virus.

62.

Monoclonal antibodies

a)

are always IgE.

b)

have the same variable regions.

c)

usually recognize several epitopes.

d)

are usually of different classes.

e)

All of the answer choices are correct.

63.

In addition to lysis, animal viruses may exit the host cell by

a)

endocytosis.

b)

fusion.

c)

budding.

d)

fission.

e)

extrusion.

64.

When a non-enveloped animal virus adsorbs to the host cell with its protein spikes, the virions are taken into the cell by the process of

a)

penetration.

b)

budding.

c)

production.

d)

endocytosis.

e)

fusion.

65.

Once inside the host cell, phage DNA

a)

is replicated.

b)

is transcribed.

c)

may get degraded by bacterial nucleases.

d)

may integrate into the host chromosome.

e)

All of the choices are correct.

66.

Bacteria may survive phagocytosis by

a)

avoiding recognition and attachment of lymphocytes AND lysing the phagosome.

b)

preventing encounters with phagocytes AND preventing fusion of two phagosomes.

c)

preventing fusion of the lysosome with the phagosome AND mimicking host molecules.

d)

preventing fusion of the lysosome with the phagosome AND lysing the phagosome.

e)

lysing the phagosome AND mimicking host molecules.

67.

Select the correct sequence for proving Koch's postulates.

1. The microorganism must be recovered from the experimentally infected hosts.

2. The microorganism must be present in every case of the disease.

3. The same disease must be produced when a pure culture of the microorganism is introduced into susceptible hosts.

4. The microorganism must be grown in pure culture from diseased hosts.

a)

1, 2, 3, 4

b)

2, 4, 3, 1

c)

4, 3, 1, 2

d)

4, 1, 2, 3

e)

1, 3, 2, 4

68.

A phage that replicates inside the host cell and then lysis its host during its release is a

a)

lysogenic phage.

b)

latent phage.

c)

virulent or lytic phage.

d)

temperate phage.

e)

dormant phage.

69.

C5a peptidase

a)

is a virulence factor AND is a molecule promoting chemotaxis.

b)

synthesizes C5a.

c)

is produced by the host cell in response to infection.

d)

is a molecule promoting chemotaxis.

e)

is a virulence factor.

70.

Species of both Shigella and Streptococcus

a)

invade host cells AND cause a rash.

b)

cause diarrhea AND are delivered by flea bites.

c)

invade host cells AND produce a toxin.

d)

produce a toxin AND cause a rash.

e)

are delivered via flea bites AND produce a toxin.

71.

The site at which a virus has infected and subsequently lysed the infected cell, releasing its progeny to infect and lyse surrounding cells, thereby forming a "clear zone," is

a)

a lyse area.

b)

a plaque.

c)

a dead zone.

d)

a zone of inhibition.

e)

a burst area.

72.

Using phages to treat a bacterial infection is an interesting idea because

a)

a single phage can be genetically engineered to infect many different species of bacteria.

b)

lysed bacteria pose no threat to a person's health.

c)

a single type of phage can destroy a wide range of strains of the same pathogen

d)

of the increasing problem of antibiotic resistance in people.

e)

of the increasing problem of antibiotic resistance in pathogens.

73.

The common species name of the virus is frequently based on the

a)

shape of the viral nucleocapsid.

b)

geographic area it is found.

c)

presence or absence of a nuclear membrane.

d)

type of nucleic acid it contains.

e)

disease the virus causes.

74.

Adhesins are

a)

exotoxins AND are involved in the first step of the infectious process.

b)

are exotoxins OR are endotoxins.

c)

often found at the tip of pili AND are endotoxins.

d)

involved in the first step of the infectious process AND are often found at the tip of pili.

e)

involved in the first step of the infectious process AND are endotoxins.

75.

Viruses that infect bacteria are referred to as

a)

bacteriophages.

b)

virophages.

c)

viralcidens.

d)

bacterialogens.

e)

bacteriocidins.

76.

An infection in which the virus is continually present in the body is referred to as

a)

balanced.

b)

persistent.

c)

acute.

d)

determinant.

e)

fatal.

77.

Virulent pathogens are

a)

more likely to cause severe disease.

b)

more likely to cause disease.

c)

most likely normal microbiota.

d)

more likely to be opportunists.

e)

unable to cause disease.

78.

The infectious dose

a)

is the same for all bacteria but varies for viruses.

b)

is defined as the number of microbes needed to kill the host.

c)

may be 10–100 cells for Salmonella.

d)

is defined as the number of microbes needed to cause infection.

e)

is the same for all microorganisms.

79.

Opportunists or opportunistic pathogens

a)

are never normal microbiota.

b)

take advantage of special circumstances.

c)

are usually saprophyte, like fungi.

d)

are usually mutualistic.

e)

always cause disease.

80.

People who carry and may spread pathogenic organisms without any apparent signs or symptoms of illness are called

a)

opportunists.

b)

mutualists.

c)

secondary infectors.

d)

primary infectors.

e)

carriers.