Deck 27: Environmental Microbiology

Question 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

Answer 1

A

Question 2

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

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

Answer 2

E

Question 3

All of the following organisms are involved in carbon fixation EXCEPT

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

Answer 3

B

Question 4

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

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

Question 5

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

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

Question 6

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 7

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

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

Question 8

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 9

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 10

All of the following are used in secondary sewage treatment EXCEPT

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

Question 11

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

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

Question 12

All of the following are true of mycorrhizae EXCEPT

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

Question 13

Which of the following is required for composting?

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

Question 14

Biochemical oxygen demand is a measure of the

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

Question 15

All of the following are habitats for extremophiles EXCEPT

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

Question 16

What stage of sewage treatment produces methane?

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

Question 17

Figure 27.1

Which term in Figure 27.1 describes step V?

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

Question 18

Figure 27.1

Which step in Figure 27.1 represents anaerobic respiration?

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

Question 19

NH₃ → NO₂-

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

Question 20

Which of the following requires aerobic conditions?

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

Question 21

Filtration to remove protozoa occurs in

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

Question 22

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

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

Question 23

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 24

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

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

Question 25

Which of the following is an assimilation process?

A) Redwood tree: SO42- → Sulfhydryl groups of amino acids
B) Desulfovibrio: SO42- → H2S
C) Thiobacillus: H2S → S0
D) Proteus: Sulfhydryl-containing amino acids → H2S
E) Photosynthetic bacteria: H2S → S0

Question 26

The product of which process contains the highest BOD?

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

Question 27

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

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

Question 28

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) b and c
E) a and b

Question 29

Residual chlorine must be maintained in

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

Question 30

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

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

Question 31

Sedimentation of sludge occurs in

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

Question 32

Zoogloea form flocculent masses in

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

Question 33

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

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

Question 34

Which of the following do NOT fix atmospheric nitrogen?

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

Question 35

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

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

Question 36

Drinking water supplies are routinely tested for the presence of

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

Question 37

Which of the following is NOT characteristic of fecal coliforms?

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

Question 38

The release of phosphate-containing detergents into a river would

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

Question 39

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

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

Question 40

Aerobic respiration occurs in

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

Question 41

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

Question 42

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

Question 43

Bacteria that are used as biosensors

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

Question 44

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

Question 45

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

Question 46

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

Question 47

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

Question 48

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

Question 49

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

Question 50

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

Question 51

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