Deck 24: The Wave Nature of Light

Question 1

Choose the one alternative that best completes the statement or answers the question.
All of the following are fuels produced by microorganisms EXCEPT

A) oil from algae.
B) hydrogen.
C) methane.
D) cellulose.
E) ethanol.

Answer 1

D

Question 2

In Figure 28.1, assume the cells are producing penicillin which is collected during the idiophase. When would you be able to collect the penicillin?

A) a
B) b
C) c
D) d

Answer 2

C

Question 3

All of the following are advantages of a bioreactor instead of a flask culture EXCEPT

A) uniform aeration and mixing.
B) instrumentation for monitoring environmental conditions.
C) aseptic sampling.
D) larger culture volumes can be grown.
E) None of the answers is correct; all of these are advantages of using a bioreactor instead of a flask culture.

Answer 3

E

Question 4

Choose the one alternative that best completes the statement or answers the question.
Commercial sterilization differs from complete sterilization in that commercial sterilization

A) employs a higher temperature.
B) may result in the survival of fungal spores.
C) kills only bacteria.
D) may result in the survival of thermophiles.
E) kills all microorganisms.

Question 5

Choose the one alternative that best completes the statement or answers the question.
Spoilage of canned foods due to inadequate processing, NOT accompanied by gas production, is

A) spoilage by mesophilic bacteria.
B) thermophilic anaerobic spoilage.
C) putrefactive anaerobic spoilage.
D) caused by acid-tolerant fungi.
E) flat sour spoilage.

Question 6

Choose the one alternative that best completes the statement or answers the question.
Which of the following pairs is mismatched?

A) Lactobacillus  yogurt
B) Propionibacterium  Swiss cheese
C) Bacillus  beer
D) Penicillium  blue cheese
E) Acetobacter  vinegar

Question 7

In Figure 28.1, assume the cells are your desired product and you want to maintain a continuous culture. When would you harvest cells to maximize your yield?

A) a
B) b
C) c
D) d

Question 8

Choose the one alternative that best completes the statement or answers the question.
Spoilage of canned foods stored at high temperatures, accompanied by gas production, is

A) spoilage by mesophilic bacteria.
B) thermophilic anaerobic spoilage.
C) caused by acid-tolerant fungi.
D) putrefactive anaerobic spoilage.
E) flat sour spoilage.

Question 9

Microbial products can be improved by all of the following EXCEPT

A) genetically modifying strains.
B) isolating new strains.
C) mutating existing strains.
D) modifying culture conditions.
E) sterilization.

Question 10

In Figure 28.1, assume that a secondary metabolite is your desired product. When would you be able to obtain it?

A) a
B) b
C) c
D) d

Question 11

Which of the following reactions is performed by yeast in wine-making? A) carbon dioxide $\rightarrow$ sucrose
B) ethanol $\rightarrow$ acetic acid
C) sugar $\rightarrow$ ethanol
D) malic acid $\rightarrow$ lactic acid
E) sugar $\rightarrow \mathrm { CO } _ { 2 } + \mathrm { H } _ { 2 } \mathrm { O }$

Question 12

Commercial sterilization of processed canned foods uses a 12D treatment which is based upon a theoretical population of $10 ^ { 12 }$ C. botulinum endospores in a can of food. After treatment, there would theoretically be how many endospores left?

A) 1 endospore
B) 100 endospores
C) 12 endospores
D) 10 endospores
E) 0 endospores

Question 13

Which of the following microorganisms is usually used in the fermentation of alcoholic beverages?

A) Penicillium
B) Saccharomyces
C) Rhizopus
D) Lactobacillus
E) Propionobacterium

Question 14

Which of the following reactions makes wine less acidic? A) sugar $\rightarrow \mathrm { CO } _ { 2 } + \mathrm { H } _ { 2 } \mathrm { O }$
B) ethanol $\rightarrow$ acetic acid
C) carbon dioxide $\rightarrow$ sucrose
D) sugar $\rightarrow$ ethanol
E) malic acid $\rightarrow$ lactic acid

Question 15

Choose the one alternative that best completes the statement or answers the question.
A baker forgets to put yeast in his bread dough. Which of the following do you expect to happen to the bread as a result?

A) The bread will have a sour taste.
B) It will take longer to bake.
C) Bacterial contaminants will now be able to grow.
D) The bread will not rise.
E) The bread will look normal but will be tough.

Question 16

Choose the one alternative that best completes the statement or answers the question.
Microorganisms play an active role in the formation of industrial products. Which of the following is mismatched?

A) Rhizobium - increases nitrogen in the soil
B) Penicillium - treatment of disease
C) Saccharomyces cerevisiae - for fermentation
D) Bacillus thuringiensis - insecticide
E) algae - citric acid

Question 17

All of the following are true of irradiation methods used for food preservation and sterilization EXCEPT

A) they greatly reduce the number of pathogens present in meats and poultry.
B) they prolong shelf-life of fruits and vegetables.
C) ionizing radiation such as X rays or gamma rays is used.
D) they are used for the sterilization of many spices.
E) residual radioactivity is left behind on many foods.

Question 18

Choose the one alternative that best completes the statement or answers the question.
Which of the following is an undesirable contaminant in wine-making?

A) lactic acid bacteria
B) Saccharomyces
C) Acetobacter
D) Bacillus
E) Clostridium

Question 19

Choose the one alternative that best completes the statement or answers the question.
Which of the following pertains to an improperly canned food product on a store shelf that bulges from microbial activity?

A) thermophilic anaerobic spoilage
B) flat sour spoilage
C) hydrogen sulfide spoilage
D) mesophilic spoilage
E) bacterial soft rot

Question 20

All of the following are industrial products produced by microbes EXCEPT

A) amino acids in food supplements.
B) vitamin B12 and riboflavin.
C) industrial enzymes.
D) uranium.
E) antibiotics.

Question 21

Biomass is a renewable energy source derived from the organic matter produced by living organisms. All of the following are sources of biomass EXCEPT

A) bacteria.
B) algae.
C) landfill sites.
D) crops.
E) oxidation of metals.

Question 22

The following steps are required for making cheese. What is the second step?

A) inoculation with lactic acid bacteria
B) enzymatic coagulation of milk
C) inoculation with Penicillium
D) fermentation of curd
E) separation of curds and whey

Question 23

Aseptic packaging works to preserve foods through

A) increasing pH.
B) creation of an anaerobic environment.
C) mutation of bacterial DNA.
D) exposure to high heat.
E) creation of an anaerobic environment and high heat.

Question 24

Figure $28.3$

Which of the growth curves in Figure 28.3 will give the highest yield of a secondary metabolite?

A) a
B) b
C) c
D) d
E) e

Question 25

As cheese ages, it gets

A) more alcoholic.
B) saltier.
C) more whey.
D) more protein.
E) more acidic.

Question 26

Microorganisms themselves are commercial products. Which of the following microbes is available as a product sold in retail stores?

A) Saccharomyces
B) Lactobacillus
C) Bacillus thuringiensis
D) Rhizobium
E) All of these organisms can be found in various commercial products.

Question 27

Figure $28.3$

Figure 28.3 shows the growth curves of Acetobacter under different conditions. Which culture would produce the highest amount of the primary metabolite acetic acid?

A) a
B) b
C) c
D) d
E) e

Question 28

What role do lactic acid bacteria play in cheese production?

A) providing characteristic flavor and smell
B) production of holes in Swiss cheese
C) curd formation
D) ripening the cheese
E) Lactic acid bacteria carry out each of these roles in cheese production.

Question 29

Which of the following microbes produces a natural biopesticide?

A) Bacillus thuringiensis
B) Saccharomyces cerevisiae
C) Lactobacillus buggaricus
D) Thiobacillus ferroxidans
E) Penicillium chryssogenum

Question 30

Thiobacillus ferrooxidans is used for the recovery of _________ from ore.

A) copper
B) sulfuric acid
C) gold
D) iron
E) sulfur

Question 31

All of the following foods are produced using microbial fermentations EXCEPT

A) ketchup.
B) sauerkraut.
C) coffee.
D) sour cream.
E) yogurt.

Question 32

All of the following are industrial enzymes made by microbial fermentations EXCEPT

A) glucose isomerase.
B) rennin.
C) amylases.
D) vitamin C.
E) proteases.

Question 33

All of the following are industrial products produced using microbial fermentations EXCEPT

A) riboflavin.
B) aspartame.
C) citric acid.
D) monosodium glutamate.
E) saccharin.

Question 34

Aseptic packaging utilizes which of the following to sterilize laminated paper or plastic prior to filling with food?

A) X rays
B) hot HCl solution
C) gamma radiation
D) autoclave
E) hot hydrogen peroxide solution

Question 35

You are growing Bacillus subtilis in a bioreactor and notice that the growth rate has slowed and the pH has decreased. What could you add?

A) glucose
B) lactic acid
C) lactose
D) oxygen
E) peptides

Question 36

You are growing Bacillus subtilis in a bioreactor and notice that the growth rate has slowed and the pH has decreased. You suspect the bacteria are

A) using the Krebs cycle.
B) photosynthesizing.
C) fermenting.
D) dead.
E) using proteins.

Question 37

Canning preserves food

A) by exposure to high heat.
B) through use of aseptic packaging.
C) by exposure to high pH.
D) by exposure to radiation.
E) by exposure to chemicals.

Question 38

What process does yeast use to produce ethanol for automobile fuel from corn?

A) photosynthesis
B) fermentation
C) oxidation
D) anaerobic respiration
E) the Krebs cycle

Question 39

Canning works to preserve foods through

A) exposure to high heat.
B) creation of an anaerobic environment.
C) mutation of bacterial DNA.
D) creation of an anaerobic environment and high heat.
E) increasing pH.

Question 40

All of the following are uses for radiation EXCEPT

A) killing of insect eggs and larva.
B) inactivation of Trichinella larvae.
C) prevention of sprouting.
D) heating cold food.
E) sterilizing spices.

Question 41

Write 'T' if the statement is true and 'F' if the statement is false.
High-pressure processing of foods such as deli meats and precooked chicken strips targets
pathogens such as C. botulinum.

Question 42

Write 'T' if the statement is true and 'F' if the statement is false.
Rhizobium and Bradyrhizobium are mixed with peat moss to increase nitrogen fixation.

Question 43

Bioreactors are widely used for industrial fermentation. Which of the following conditions must be closely monitored for optimal fermentation? A) oxygen levels
B) temperature
C) $\mathrm { pH }$
D) both temperature and $\mathrm { pH }$
E) temperature, $\mathrm { pH }$ , and oxygen levels

Question 44

Write 'T' if the statement is true and 'F' if the statement is false.
If an industrial microbiologist works with Thiobacillus ferrooxidans, he is likely to be involved in
copper mining.

Question 45

Radiation works to preserve foods through

A) creation of an anaerobic environment.
B) exposure to high heat.
C) lethal mutation of bacterial DNA.
D) creation of an anaerobic environment and high heat.
E) increasing pH.

Question 46

All of the following are reasons for utilizing algae for biofuel production EXCEPT

A) they can utilize agriculturally poor land.
B) their main requirement is abundant light.
C) they do not take up land needed for food production.
D) they produce more energy per acre than corn.
E) they produce a nondegradable waste product.

Question 47

What will be produced if wine is aerated? A) acetic acid
B) $\mathrm { CO } _ { 2 } + \mathrm { H } _ { 2 } \mathrm { O }$
C) ethanol $+ \mathrm { CO } _ { 2 }$
D) $\mathrm { CH } _ { 4 }$
E) None of the answers is correct.

Question 48

Write 'T' if the statement is true and 'F' if the statement is false.
The production of vinegar relies on the microbial oxidation of ethanol to acetic acid.

Question 49

Write 'T' if the statement is true and 'F' if the statement is false.
Industrial canning is achieved using a pressure cooker which operates in a manner similar to an
autoclave.

Question 50

ESSAY. Write your answer in the space provided or on a separate sheet of paper.
Discuss the production of three different non-food/beverage substances that utilize microorganisms in their
production. Your discussion should include the specific microorganisms involved and their role in the
production of each substance.

Question 51

ESSAY. Write your answer in the space provided or on a separate sheet of paper.
Explain how ionizing radiation can be used to preserve foods. Discuss its advantage over canning as a method
of preservation.

Question 52

Write 'T' if the statement is true and 'F' if the statement is false.
The longer interior-ripened cheeses are permitted to ripen, the milder the taste of the cheese.

Question 53

Xanthan used in household products is produced by bacteria

A) that were irradiated to mutate them.
B) that were genetically modified.
C) that are plant pathogens.
D) selected for their ability to utilize lactose.
E) selected for their ability to utilize lactose and that are plant pathogens.

Question 54

Write 'T' if the statement is true and 'F' if the statement is false.
Mesophilic bacteria grow best at temperatures of 60°C.

Question 55

Write 'T' if the statement is true and 'F' if the statement is false.
A large industry exists based on the synthesis of amino acids by microorganisms.

Question 56

Write 'T' if the statement is true and 'F' if the statement is false.
The blue-green clumps observed in Roquefort cheese are a result of mold growth.

Question 57

ESSAY. Write your answer in the space provided or on a separate sheet of paper.
Vessels used for industrial fermentation reactions are known as bioreactors. Explain the difference between
batch production and continuous flow production using a bioreactor.

Question 58

Write 'T' if the statement is true and 'F' if the statement is false.
Vitamins A, B12, and E are commonly produced by microorganisms.