Deck 27: Environmental Microbiology

Question 1

Which wastewater treatment process produces BOD- containing effluent used for irrigation?

A) secondary sewage treatment
B) primary sewage treatment
C) anaerobic sludge digestion
D) water treatment
E) tertiary sewage treatment

Answer 1

A

Question 2

Which of the following is required for composting?

A) periodic turning or raking of the compost pile
B) addition of non- biodegradable materials
C) constant anaerobic conditions
D) addition of nitrogen and phosphorus sources
E) addition of thermophilic microbes

Answer 2

A

Question 3

Which of the following organisms is using sulfur as a source of energy?

A) Photosynthetic bacteria: H₂S -S⁰
B) Desulfovibrio: SO₄^2- -H₂S
C) Thiobacillus: H₂S -S⁰
D) Redwood tree: SO₄^2- -Amino acids
E) Proteus: Amino acids -H₂S

Answer 3

C

Question 4

Figure 27.1

Which step in Figure 27.1 represents the following reaction: amino acid (- NH₂) -NH₃?

A) I
B) II
C) III
D) IV
E) V

Question 5

Filtration to remove protozoa occurs in

A) secondary sewage treatment.
B) tertiary sewage treatment.
C) anaerobic sludge digestion.
D) water treatment.
E) primary sewage treatment.

Question 6

For the biogeochemical cycles of the following elements, which does NOT have an atmospheric cycle?

A) sulfur
B) phosphorus
C) nitrogen
D) carbon

Question 7

Figure 27.2

Where are photosynthetic bacteria most likely to be found in Figure 27.2?

A) a
B) b
C) c
D) a and b
E) b and c

Question 8

6H₂S + 6CO₂ ^light 6S⁰ + glucose

A) takes place under aerobic conditions.
B) takes place under anaerobic conditions.
C) The amount of oxygen does not make any difference.

Question 9

Adding untreated sewage to a freshwater lake would cause the biochemical oxygen demand to

A) decrease.
B) increase.
C) stay the same.
D) The answer cannot be determined based on the information provided.

Question 10

Which one of the following processes in sewage treatment requires bacterial metabolism?

A) sedimentation
B) primary treatment
C) removal of BOD
D) chlorination
E) None of the answers is correct.

Question 11

All of the following organisms are involved in carbon fixation EXCEPT

A) green and purple sulfur bacteria.
B) mycorrhizae.
C) cyanobacteria.
D) algae.
E) lichens.

Question 12

Figure 27.1

Which of the following terms describes step III in Figure 27.1?

A) nitrogen fixation
B) nitrification
C) assimilation
D) denitrification
E) ammonification

Question 13

Untreated sewage is released into a river. Which of the following statements is FALSE?

A) The untreated sewage decreases the dissolved oxygen.
B) The untreated sewage is a health hazard.
C) The untreated sewage increases the BOD.
D) The untreated sewage kills bacteria.
E) All of the statements are true.

Question 14

Which of the following terms describes NO₃^- -NO₂^- -N₂O -N₂?

A) nitrogen fixation
B) anaerobic respiration
C) nitrification
D) denitrification
E) ammonification

Question 15

All of the following are habitats for extremophiles EXCEPT

A) 100°C water.
B) a salt- evaporating pond.
C) the Atlantic Ocean.
D) an acid mine wash.
E) inside rock.

Question 16

The product of which process contains the highest BOD?

A) primary sewage treatment
B) tertiary sewage treatment
C) water treatment
D) anaerobic sludge digestion
E) secondary sewage treatment

Question 17

In the ONPG and MUG test for fecal coliforms, a sample that is positive for E. coli will be

A) negative for ONPG; non- fluorescent in UV light.
B) positive for ONPG; fluorescent in UV light.
C) negative for ONPG; fluorescent in UV light.
D) positive for ONPG; non- fluorescent in UV light.

Question 18

Drinking water supplies are routinely tested for the presence of

A) Vibrio.
B) Giardia.
C) fecal coliforms.
D) fecal viruses.
E) Cryptosporidium.

Question 19

Which of the following is NOT a symbiotic pair of organisms?

A) elk and rumen bacteria
B) orchid and mycorrhizae
C) sulfur and Thiobacillus
D) onions and arbuscules
E) bean plant and Rhizobium

Question 20

In freshwater lakes and ponds, the majority of photosynthetic microbes are located in the zone(s).

A) profundal
B) benthic and profundal
C) littoral
D) benthic
E) limnetic

Question 21

In the early 1900s, cities such as Philadelphia reduced the incidence of typhoid fever by

A) requiring residents to boil drinking water.
B) isolating human carriers.
C) filtering municipal drinking water through sand- bed filters.
D) using tertiary water treatment systems.
E) mass vaccination of residents.

Question 22

Figure 27.1

Which term in Figure 27.1 describes step V?

A) ammonification
B) dissimilation
C) denitrification
D) nitrification
E) nitrogen fixation

Question 23

NH₃ -NO₂^-

A) takes place under aerobic conditions.
B) takes place under anaerobic conditions.
C) The amount of oxygen does not make any difference.

Question 24

Bacteria can increase the Earth's temperature by

A) providing nutrients for plant growth.
B) generating a great deal of heat in metabolism.
C) producing CH₄, which is a greenhouse gas.
D) oxidizing CH₄.
E) using the greenhouse gas CO₂.

Question 25

Sedimentation of sludge occurs in

A) secondary sewage treatment.
B) tertiary sewage treatment.
C) water treatment.
D) primary sewage treatment.
E) anaerobic sludge digestion.

Question 26

Which wastewater treatment process is responsible for removal of most of the BOD in sewage?

A) tertiary sewage treatment
B) secondary sewage treatment
C) water treatment
D) anaerobic sludge digestion
E) primary sewage treatment

Question 27

Figure 27.1

Which step in Figure 27.1 represents anaerobic respiration?

A) I
B) II
C) III
D) IV
E) V

Question 28

Which of the following do NOT fix atmospheric nitrogen?

A) mycorrhizae
B) lichens
C) cyanobacteria
D) Frankia
E) Azotobacter

Question 29

Zoogloea form flocculent masses in

A) secondary sewage treatment.
B) water treatment.
C) tertiary sewage treatment.
D) anaerobic sludge digestion.
E) primary sewage treatment.

Question 30

Bacteria that emit light can be used as biosensors because they

A) migrate to hazardous chemical.
B) have the lux gene.
C) do not emit light in the presence of a hazardous chemical.
D) have FMN.
E) degrade hazardous chemicals.

Question 31

Which of the following is an assimilation process?

A) Thiobacillus: H₂S -S⁰
B) Photosynthetic bacteria: H₂S -S⁰
C) Redwood tree: SO₄^2- -Amino acids
D) Proteus: Amino acids -H₂S
E) Desulfovibrio: SO₄^2- -H₂S

Question 32

Figure 27.2

Where are the benthic microbes such as Desulfovibrio and Clostridium most likely to be found in Figure 27.2?

A) a
B) b
C) c
D) a and b
E) b and c

Question 33

Bioremediation of petroleum

A) takes place under aerobic conditions.
B) takes place under anaerobic conditions.
C) The amount of oxygen does not make any difference.

Question 34

The guano deposited by seabirds is used a source for which of the following fertilizer components?

A) carbonate
B) nitrate
C) phosphate
D) potassium
E) sulfate

Question 35

Which of the following is mismatched?

A) SO₄^2- + 10H⁺ -H₂S + 4H₂O - Desulfovibrio
B) 6CO₂ + 6H₂O -C₆H₁₂O₆ + 6O₂ - Clostridium
C) N₂ + 6H⁺ -2NH₃ - Beijerinckia
D) CO₂ + 4H₂ -CH₄ + 2H₂O - Methane- producing bacteria
E) Fe²⁺ -Fe³⁺ - Thiobacillus ferrooxidans

Question 36

What stage of sewage treatment produces methane?

A) sludge digestion
B) primary treatment
C) secondary treatment
D) tertiary treatment
E) None of the stages of sewage treatment produce methane.

Question 37

Figure 27.1

Nitrification is beneficial to farmers. It is represented by which step in Figure 27.1?

A) I
B) II
C) III
D) IV
E) V

Question 38

Which of the following is NOT characteristic of fecal coliforms?

A) lactose- fermenting
B) non- spore forming
C) rod- shaped
D) pathogenic
E) gram- negative

Question 39

Residual chlorine must be maintained in

A) anaerobic sludge digestion.
B) water treatment.
C) primary sewage treatment.
D) secondary sewage treatment.
E) tertiary sewage treatment.

Question 40

Which of the following requires aerobic conditions?

A) water treatment
B) secondary sewage treatment
C) nitrogen fixation
D) sludge digestion
E) primary sewage treatment

Question 41

The bacteriological safety of drinking water is determined by testing water samples for the presence of human pathogens.

Question 42

Nitrogen fixation by bacteria occurs only in the root nodules of leguminous plants.

Question 43

In water treatment, the purpose of flocculation is to remove microbes, such as Giardia and
Cryptosporidium.

Question 44

Aerobic respiration occurs in

A) tertiary sewage treatment.
B) anaerobic sludge digestion.
C) secondary sewage treatment.
D) water treatment.
E) primary sewage treatment.

Question 45

Based on your knowledge of extremophiles and endoliths, describe the characteristics you would expect of microorganisms capable of living on Mars or other non- Earth environments.

Question 46

A newspaper headline reported "Algal Bloom Kills Fish." What actually caused fish death, given that the algae were not toxic? What could have caused the algal bloom?

Question 47

The dense growth of algae in an algal bloom leads to increased oxygen levels in lakes that enhance the habitat for fish.

Question 48

The release of phosphate- containing detergents into a river would

A) improve the water quality.
B) increase algal growth.
C) kill algae.
D) kill bacteria.
E) None of the answers is correct.

Question 49

All of the following are used in secondary sewage treatment EXCEPT

A) bulking and floc formation.
B) aeration.
C) activated sludge.
D) anaerobic digestion.
E) trickling filters.

Question 50

Bioremediation involves the use of microbes to degrade or detoxify pollutants.

Question 51

The BOD is a measurement of the amount of bacteria present before and after the sewage treatment process.

Question 52

Biochemical oxygen demand is a measure of the

A) amount of organic matter present in a water sample.
B) amount of oxygen present in a water sample.
C) amount of undissolved solid matter present in a water sample.
D) number of bacteria present in a water sample.
E) amount of nitrogen in a water sample.

Question 53

The water from tertiary sewage treatment can be used as drinking water.

Question 54

The purpose of tertiary sewage treatment is to remove all of the phosphorus, nitrogen, and BOD left from secondary treatment.

Question 55

All of the following are true of mycorrhizae EXCEPT

A) ectomycorrhizae form a mantle over plant roots.
B) an example is the food delicacy truffles.
C) they are fungi that form beneficial relationships with plants.
D) the vesicular- arbuscular mycorrhizae are a type of ectomycorrhizae.
E) they enable plants to absorb soil nutrients.

Question 56

Microorganisms in deep- sea vents and caves serve as autotrophic primary producers in the absence of sunlight.

Question 57

In small communities lacking municipal sewage systems, sewage is treated in septic systems or oxidation ponds.