Deck 25: Applied and Environmental Microbiology

Question 1

Which of the following results when ethanol is allowed to oxidize to acetic acid following the fermentation of fruit, grain, or vegetables?

A) champagne
B) vinegar
C) beer
D) malt
E) wine

Answer 1

B

Question 2

Which of the following is a lactic acid bacterium used in the production of food?

A) Aspergillus oryzae
B) Leuconostoc
C) Penicillium
D) Gluconobacter
E) Saccharomyces cerevisiae

Answer 2

B

Question 3

The eukaryote is a common food contaminant that can lead to foodborne illness.

A) Listeria monocytogenes
B) Yersinia enterocolitica
C) Vibrio vulnificus
D) Toxoplasma gondii
E) Campylobacter jejuni

Answer 3

D

Question 4

Sulfur dioxide is added to ʺmustʺ in the production of wine to

A) prevent tannins from leaching out of wood into the fermenting wine.
B) allow more control over the fermentation process.
C) improve the flavor.
D) provide a necessary nutrient for the fermentation process.
E) both enhance flavor and promote fermentation.

Question 5

Control of the fermentation of foods to produce the desired product commonly involves

A) use of a starter culture.
B) adding required nutrients for microbial growth.
C) careful choice of foodstuffs.
D) pretreating the food by boiling.
E) both pretreating the food by boiling and adding required nutrients for microbial growth.

Question 6

The fermentation product known as silage is

A) a meat product.
B) a means of making plant materials more appealing to livestock.
C) a step in the production of brandy.
D) a means of food preservation.
E) made from milk.

Question 7

A researcher studying the impact of agricultural pesticides on native plants discovers a bacterium capable of degrading small amounts of a specific pesticide. The researcher then modifies the bacterial species in the lab to increase the rate of pesticide degradation. This research represents

A) environmental microbiology.
B) applied microbiology.
C) food microbiology.
D) both food microbiology and environmental microbiology.
E) both applied microbiology and environmental microbiology.

Question 8

Which of the following is used in both food production and industrial fermentation?

A) Listeria monocytogenes
B) Bacillus thuringiensis
C) Escherichia coli
D) Saccharomyces cerevisiae
E) Pseudomonas syringae

Question 9

Pickling is an effective means of food preservation involving

A) increasing oxygen content.
B) increasing salt concentration.
C) reducing oxygen content.
D) reducing pH.
E) increasing salt concentration or reducing pH or both.

Question 10

An intrinsic factor of food that can determine whether spoilage occurs is

A) the water content.
B) the storage temperature.
C) storage packaging.
D) the amount of preservatives added.
E) the degree of processing.

Question 11

What is the significance of the industrial practice of waiting for cultures to enter the stationary phase of growth before harvest?

A) An optimal combination of primary and secondary metabolites is being produced.
B) The desired primary metabolites are produced in stationary phase.
C) Secondary metabolites are often the desired product, and are only produced in stationary phase.
D) The cells are at peak metabolic activity.
E) Potential toxins from log phase growth have been depleted.

Question 12

Which of the following items that are commonly added during food preparation can be considered a preservative?

A) garlic
B) meat broth
C) apple juice
D) yeast
E) whey

Question 13

Which of the following pairs is MISMATCHED?

A) brandy; fruit juice
B) white wine; hops
C) vodka; potatoes
D) beer; malt
E) whiskey; cereal grains

Question 14

Sugar and salt act as preservatives by

A) drawing water out of food.
B) inhibiting bacterial enzymes.
C) producing oils that inhibit bacterial growth.
D) killing endospores.
E) inhibiting DNA replication.

Question 15

Food contaminated with may contain a potent neurotoxin.

A) Salmonella spp.
B) Shigella spp.
C) Listeria monocytogenes
D) Escherichia coli
E) Clostridium botulinum

Question 16

Which of the following pairs of industrial microbial products and their uses is MISMATCHED?

A) streptokinase; dissolving blood clots
B) gluconic acid; release of cellulose from flax to make linen
C) phenylalanine; the sweetener aspartame
D) indigo; blue jeans
E) citric acid; antioxidant in food

Question 17

Why are ʺfortifiedʺ foods more likely to spoil than are unfortified foods?

A) The vitamins require a neutral pH environment, which is suitable for many microbes.
B) The addition of vitamins or minerals makes the food more nutritious for microbes as well as humans.
C) The addition of nutrients creates an osmotic environment suitable for a wide range of microbes.
D) Every step of modification or manipulation of food increases the chance for contamination.
E) Vitamins are added to ʺfortifiedʺ foods by adding the microbes that produce the vitamins to the food item.

Question 18

Why is the pasta you buy from the grocery store shelf considered a nonperishable food?

A) It was sterilized during preparation.
B) It has a low nutritional content.
C) Microbes present in the pasta inhibit the growth of harmful microbes.
D) Various preservative chemicals are added.
E) The low moisture content prevents microbial growth.

Question 19

Which of the following methods of preserving food sterilizes it?

A) drying
B) canning
C) lyophilization
D) pasteurization
E) gamma radiation

Question 20

Which of the following food products is prepared by the fermentation of cabbage?

A) refined sugar
B) kimchi
C) pasteurized milk
D) tea
E) sorbet

Question 21

What was the first substance produced by microorganisms to be used pharmaceutically?

A) human insulin
B) penicillin
C) interferons
D) streptokinase
E) taxol

Question 22

Which of the following is the correct sequence of microbial associations from smallest to largest?

A) communities, microhabitats, ecosystem, guilds, populations
B) populations, guilds, communities, microhabitats, ecosystem
C) ecosystem, populations, communities, microhabitats, guilds
D) populations, communities, microhabitats, ecosystem, guilds
E) populations, communities, ecosystem, guilds, microhabitats

Question 23

Which of the following bacteria is a common soil bacterium that may cause disease in humans?

A) Aspergillus oryzae
B) Cyanobacteria
C) Lactoccocus cremoris
D) Bacillus anthracis
E) Streptomyces scabies

Question 24

Green and purple sulfur bacteria will carry out anaerobic photosynthesis primarily in

A) zone 1.
B) zone 2.
C) zone 3.
D) zone 4.
E) both zones 1 and 2.

Question 25

Which of the following may result from eating shellfish?

A) norovirus infection
B) polio
C) botulism
D) salmonellosis
E) paralysis

Question 26

A specific example of bioremediation is

A) the purification of water for drinking.
B) the treatment of wastewater.
C) acid mine drainage.
D) the treatment of sludge.
E) the degradation of crude oil spilled into the Gulf of Mexico.

Question 27

Streptokinase is useful for which of the following?

A) insecticide
B) biosensors
C) producing antibiotics
D) dissolving blood clots
E) cheese production

Question 28

Potable water is water that

A) is transferred from one place to another.
B) contains biosensors.
C) contains low amounts of microorganisms and is considered safe to drink.
D) contains a dangerous number of microorganisms.
E) is considered safe to drink because it is completely sterile.

Question 29

During treatment of water to make it potable, about 90% of the microbes are removed

A) by treatment with biosensors.
B) by treatment with chlorine or ozone.
C) in the sedimentation step.
D) in the filtration step.
E) by preliminary fermentation.

Question 30

Which of the following is an application of proteases?

A) cheese
B) vodka
C) wine
D) indigo
E) meat tenderizer

Question 31

Which of the following microorganisms is the most commonly used indicator organism for water quality testing?

A) Escherichia coli
B) Salmonella spp.
C) Streptococcus thermophilus
D) Hepatitis A virus
E) Shigella spp.

Question 32

Which of the following infectious diseases is currently of greatest concern as a biological weapon?

A) cholera
B) botulism
C) the plague
D) anthrax
E) smallpox

Question 33

Which of these microbial products is needed to produce ʺgasoholʺ?

A) ethanol
B) citric acid
C) hyaluronidase
D) methanol
E) aspartame

Question 34

What type of reactions take place in the portion of the sulfur cycle indicated in the figure?

A) denitrification
B) fermentation
C) dissimilation
D) oxidation-reduction
E) carbon fixation

Question 35

Which of the following statements concerning the phosphorus cycle in bacteria is TRUE?

A) The molecule is converted to a gaseous state and is lost to the environment.
B) It is the most important process for synthesizing proteins and nucleic acids.
C) The molecule cycles between different organic molecules.
D) The molecule changes from insoluble to soluble forms.
E) The molecule alternates among several oxidative states.

Question 36

Which of the following sets of characteristics describes the highest level of threat potential from biological weapons?

A) a microbe that can be introduced into food during packaging and withstands refrigerator temperatures but not typical cooking temperatures
B) a waterborne toxin that is easily introduced into public water supplies and does not replicate in humans
C) a pathogen of livestock transmitted by contact with infected animals but not infected people
D) a pathogen of wheat that could be delivered using crop dusters
E) a human pathogen easily produced as an aerosol and transmissible by respiratory aerosols

Question 37

Which of the following statements concerning the biochemical oxygen demand (BOD) is correct?

A) It is a measurement of the amount of oxygen that aerobic bacteria require to fully metabolize organic wastes in water.
B) It is a measure of the amount of oxygen in water.
C) It is used as a bioreceptor index.
D) It is a filter system to purify drinking water.
E) It is proportional to how potable water is.

Question 38

Industrial fermentation and fermentation in food production

A) are processes in which sugar or protein is oxidized to produce alcohols or acids.
B) are both processes in which sugars are oxidized to alcohols or acids.
C) make use of the same microorganisms.
D) use entirely different starting material.
E) use entirely different microorganisms.

Question 39

A new industrial park in your community dumps its wastewater into a large aerated pond, to which nutrients are added. The water from this pond makes its way into a nearby marsh, which eventually drains into a slow-moving stream. This is an example of

A) natural bioremediation.
B) artificial bioremediation.
C) bioreporter use.
D) a method to make potable water.
E) natural fermentation.

Question 40

Chlorinated water contains

A) no bacteria at all.
B) no cysts.
C) a decreased microbial load.
D) no viruses.
E) no endospores.

Question 41

Through recombinant DNA technology, many plants now can manufacture their own Bt toxin, which improves fermentation.

Question 42

Garlic contains an antimicrobial substance called (allicin/penicillin/streptomycin).

Question 43

Soy sauce is made using

A) Acetobacter.
B) Aspergillus oryzae and Saccharomyces.
C) Saccharomyces.
D) Aspergillus oryzae and Lactobacillus.
E) Lactoccocus cremoris.

Question 44

Which of the following would be most effective in reducing the amount of CO2 in the atmosphere?

A) cyanobacteria
B) nitrogen fixers
C) anaerobic microbes
D) heterotrophic organisms
E) fungi

Question 45

Most microbes need an environment that has a water activity of at least 0.90.)

Question 46

A common source of antibiotics is

A) Streptococcus thermophilus.
B) Aspergillus oryzae and Lactobacillus.
C) Lactoccocus cremoris.
D) Acetobacter.
E) Streptomyces.

Question 47

The definition of (fermentation/cultivation/processing) used by food microbiologists is a desirable change in food due to microbial activity.

Question 48

Bioremediation is the process of using organisms to clean up toxic, hazardous compounds by degrading them to less harmful substances.

Question 49

Pasteurization is a more rigorous process than canning.

Question 50

Cold is preferred for storing food because it retards microbial growth by slowing down metabolic processes.

Question 51

Algae and protozoa in the soil are quite hardy, and therefore, their abundance is not a useful indicator of environmental pollution.

Question 52

The process of preserving foods in brine is called (canning/pickling/salting).

Question 53

Because the same microbes are not always present on food from harvest to harvest, (fresh/natural/starter) cultures are used in the production of alcoholic beverages.

Question 54

Without the activities of microorganisms, the functioning of the Earthʹs ecosystems would cease.

Question 55

Amino acid and vitamin supplements are prepared from extracts of microbial cultures.

Question 56

The sour flavor in some fermented foods is usually the result of (acetic/benzoid/lactic) acid production.

Question 57

The starter culture used to make cheese determines the type of cheese produced

Question 58

Most of the nitrogen in the environment is in the form of nitrogen gas, which is the form used by most organisms.

Question 59

Which of the following oxidize H2S to SO4-2, the form of sulfur animals use for their metabolism?

A) Desulfovibrio
B) purple sulfur bacteria
C) Beggiatoa
D) both Beggiatoa and purple sulfur bacteria
E) both Beggiatoa and Desulfovibrio

Question 60

A few hours after a dinner party, most of the people who attended begin to suffer nausea, vomiting, and diarrhea. The food at the meal is suspected as the source, although no unusual microbes are cultured from samples of the food or from stool samples. These observations suggest they may be suffering from food (infection/intoxication).

Question 61

Benzoic acid is largely a(n) (antifungal/antiprotozoal/pickling) agent and does not affect the growth of many bacteria.

Question 62

How does water quality testing make use of environmental microbiology?

Question 63

Brandy is made by the same process as wine, but the alcohol is then concentrated by (fermentation/distillation/filtration).

Question 64

Botryococcus braunii is an alga that produces hydrocarbons at (10/20/30) percent of its dry weight and could be harvested in the future as an alternative fuel.

Question 65

Compare and contrast the two types of foodborne disease.

Question 66

Freezing food and then using a vacuum to draw off the ice crystals is called (dehydration/lyophilization/sublimation).

Question 67

The anthrax attack of fall 2001 was accomplished by mailing the agent in ordinary envelopes. This method of delivery took advantage of the ability of Bacillus anthracis to produce (aerosols/endospores/toxins).

Question 68

Compare the use of biosensors with traditional methods of determining microbial contamination.

Question 69

The organic material found in topsoil is called (humus/peat/compost).

Question 70

What are the levels of microbial associations in the environment? How do they relate to an ecosystem?

Question 71

Cyanobacteria produce a cell type known as a(n) (akinete/heterocyst/nodule) that protects nitrogenase from the exposure to oxygen.

Question 72

When one microbeʹs metabolic activities create favorable conditions for another microorganism, this is referred to as (competition/cooperation/facilitation).

Question 73

With the (batch/continuous/static) production technique, organisms are allowed to ferment their substrate until it is exhausted.

Question 74

Smallpox is considered a serious potential biological weapon, whereas anthrax has been successfully used as one. Compare and contrast their potential with regard to the criteria for assessing biological threats.