Deck 25: Environmental Microbiology

Question 1

Some microbes can survive drought by forming

A) fimbriae
B) spores
C) cysts
D) two of the above

Answer 1

D

Question 2

Nitrogen-fixing bacteria include

A) cyanobacteria
B) Clostridium
C) Klebsiella
D) all of the above

Answer 2

D

Question 3

The loss of water from pores of plant leaves is called

A) transpiration
B) respiration
C) evaporation
D) two of the above

Answer 3

A

Question 4

In the sulfur cycle many microbes convert sulfhydryl (-SH)groups to _____,which is toxic to living things.

A) hydrogen sulfate
B) hydrogen sulfide
C) HSH
D) sulfate

Question 5

Denitrification is

A) a process by which nitrates are reduced to nitrous oxide or N₂
B) a process by which nitrites are reduced to ammonia
C) a process by which amino acids are converted to pyruvate
D) largely due to aerobic environments

Question 6

Sulfur oxidation is carried out by

A) Thiobacillus
B) Desulfovibrio
C) Desulfomonas
D) Desulfotomaculum

Question 7

Producers obtain CO₂ from

A) eating other producers
B) the atmosphere
C) dead bodies
D) coal

Question 8

Which of the following statements about ecology is incorrect?

A) biosphere consists of three layers- the hydrosphere, lithosphere and atmosphere
B) communities with many populations of organisms are more stable than those with fewer populations
C) vegetative cells must have water
D) the sun is the ultimate source of energy for all organisms in any ecosystem

Question 9

The sulfur cycle is of special importance to

A) terrestrial life
B) Pseudomonas
C) proteolytic bacteria
D) aquatic life

Question 10

Which is a primary symbiotic nitrogen fixer?

A) Azotobacter
B) Rhizobium
C) Cyanobacteria
D) Clostridium

Question 11

Most denitrification is due to

A) Rhizobium
B) Azotobacter
C) Pseudomonas
D) Nitrosomonas

Question 12

Which of the following microbes is not a producer in the environment?

A) photosynthetic bacteria
B) heterotrophic bacteria
C) cyanobacteria
D) protista

Question 13

Microbes in the environment can be

A) producers
B) consumers
C) decomposers
D) all of the above

Question 14

The most usable form of sulfur by microorganisms and plants is

A) sulfide
B) sulfate
C) hydrogen sulfide
D) sulfhydryl

Question 15

The mechanism whereby Rhizobium and the legume associate is characterized by all of the following except

A) multiplies in the vicinity of legume roots
B) bacteria release proteases to digest cell wall
C) change from free-living to swarmer cells
D) swarmers invade root hairs to become bacteroids

Question 16

Nitrogenase is

A) oxygen sensitive
B) only produced by Rhizobium
C) a N₂ fixing enzyme
D) two of the above

Question 17

Nitrification is characterized by all of the following except

A) carried out by autotrophic bacteria
B) supplies plants with a usable nitrogen source
C) produces ammonia
D) nitrogen is oxidized in both of the two steps

Question 18

Nitrogen-fixing bacteria

A) oxidize ammonia to nitrates or nitrites
B) oxidize ammonia to nitrous oxide
C) reduce nitrates to nitrites
D) reduce nitrogen gas to ammonia

Question 19

Which would not be the habitat for terrestrial species of some microorganisms?

A) desert
B) tundra
C) tropical rain forest
D) freshwater lake

Question 20

Sulfate-reducing bacteria are characteristically

A) being strict anaerobes
B) Desulfovibrio
C) utilizing sulfate as a final electron acceptor
D) all of the above

Question 21

Which of the following statements about biogeochemical cycles is true?

A) not all living microbes require carbon
B) nitrogen fixing bacteria must be in association with legumes
C) Thiobacillus oxidizes hydrogen sulfide to sulfuric acid
D) Cyanobacteria are the primary symbiotic nitrogen fixer

Question 22

What results from the biological oxygen demand (BOD)being high and the water becoming anaerobic?

A) a more efficient decomposition of wastes
B) increased need for sulfur
C) decreased need for carbon
D) accumulation of wastes

Question 23

The primary producers in the ocean are

A) bacteria
B) viruses
C) phytoplankton
D) two of the above

Question 24

Which of the following symptoms is not part of sick building syndrome?

A) headache and burning eyes
B) nosebleeds and skin problems
C) dizziness and nausea
D) feeling like there is too much air

Question 25

In testing for water purity,the presumptive test would include

A) Eosin-methylene blue agar
B) lactose broth
C) nutrient agar
D) Gram stain

Question 26

The most predominant microbial group found in soil is

A) fungi
B) bacteria
C) protozoa
D) viruses

Question 27

The trickling filter system employs a bed of rocks that have been coated with

A) Sphaerotilus
B) Pseudomonas
C) Beggiatoa
D) two of the above

Question 28

Which of the following is used to control the number of microbes in the air?

A) UV light
B) triethylene glycol
C) cellulose acetate filters
D) all of the above

Question 29

The indicator organism for human pathogens in a water supply is

A) Escherichia coli
B) Salmonella typhi
C) Poliovirus
D) Staphylococcus aureus

Question 30

Phytoplankton include

A) cyanobacterteria
B) diatoms
C) dinoflagellates
D) all of the above

Question 31

In the phosphorous cycle,inorganic phosphates are converted to _____,a water-soluble nutrient used by both plants and microorganisms.

A) phosphorous
B) hydrophosphates
C) orthophosphate
D) betaphosphate

Question 32

Which is the order of purification procedures for water?

A) flocculation à chlorination à filtration à particulate settling
B) synthetic organic chemicals à particulate settling à filtration
C) chlorination à filtration à particulate settling à nitrification
D) particulate settling à flocculation treatment à filtration à chlorination

Question 33

Soil contains human pathogens,for instance

A) Clostridium tetani
B) Bacillus anthracis
C) Clostridium perfringens
D) all of the above

Question 34

Tertiary treatment of sewage could include

A) chlorine
B) UV light
C) ozone
D) all of the above

Question 35

Which of the following statements about soil is false?

A) anywhere in the soil you can find snottites
B) viruses can be used for biocontrol of insect pests in soil
C) humus is the nonliving organic matter in soil
D) carbon in the soil is continuously recycled

Question 36

Eutrophication leads to

A) a decrease in oxygen
B) plants become very dense
C) abundant nutrient enrichment
D) all of the above

Question 37

The predominant genus of microbe found in ambient air is

A) Cladosporium
B) Bacillus
C) Staphylococcus
D) Candida

Question 38

How do the ONPG and MUG test detect microorganisms in water?

A) color is changed by enzymes secreted by coliform bacteria
B) gas production in cultures of lactose broth
C) observing dark colonies of coliform organisms on EMB-lactose agar
D) colonies forming on surface of a sterile absorbent pad

Question 39

Cytophaga,found in soil,is characterized by

A) being a fungus
B) cellulose degradation
C) being strictly aerobic
D) being a protozoan decomposer

Question 40

Molds in soil serve to

A) aid in decomposition
B) aid in nitrogen-fixation
C) form a network with mycelia
D) two of the above

Question 41

What are the consequences of heat acting as a water pollutant?

A) causes silting of waterways
B) reduces light reaching plants in water
C) increases the salinity and acidity of water
D) alters habitats and kinds of organisms present

Question 42

Why are soil microorganisms so important to the nitrogen cycle? Describe the 3 roles bacteria play in the nitrogen cycle.

Question 43

Which bacteria is found in the desert and is an oil eating bacteria?

A) Halobacterium
B) Desulfurovibrio
C) Thiobacillus
D) Arthrobacter

Question 44

Which statement about septic tanks is correct?

A) pouring poisons and grease down the drain may kill the tank's beneficial microbes
B) sludge is pumped continually into a drainage leaching field
C) drainage fields last for more than 50 years
D) two of the above

Question 45

Which term is matched with its definition?

A) biotic factors - interaction of organisms with other organisms
B) ecology - all organisms in a given area with abiotic and biotic factors
C) ecosystem - organisms that are always found in a given environment
D) niche - recycling of life-essential elements and water

Question 46

Which of the following statements about extreme environments is incorrect?

A) hydrothermal vents can reach temperatures up to 350° C
B) hydrothermal fluids contain mixed communities of eubacteria and archaea
C) bacteria involved in anaerobic oxidation of methane are rare in samples
D) in different zones of a chimney wall there are different communities of microbes

Question 47

A niche includes all of the following except

A) the taxonomy of an organism
B) the role an organism plays in the ecosystem
C) an organism's use of abiotic factors in its environment
D) the interactions an organism has with other organisms

Question 48

What is the greenhouse effect? What effect might global warming have on infectious disease?

Question 49

What role do microbes play in degradation of plastics

A) microbes could be used to disintegrate plastics, like soda bottles and disposable diapers
B) bacteria could assist in making biodegradable plastics
C) bacteria could speed up the incineration process
D) two of the above

Question 50

What is the meaning of biological oxygen demand (BOD)? Why is it important for pollution? What do microbes have to do with this?

Question 51

How does Sphaerotilus interfere with an activated sludge system?

A) by coating rocks with a slimy film and decomposing organic matter
B) by removing flocculating substances
C) by proliferating in the floating matter that contaminates the effluent
D) by converting nitrates to nitrogen gas and blocking the nitrogen stripping tank

Question 52

Which term has been incorrectly matched?

A) biogeochemical cycles - recycling of life-essential elements and water
B) nitrogenase - functional nitrogen-fixing enzyme
C) swarmer cells - organisms that can invade waterlogged soils
D) nitrate - form of nitrogen most usable in plant metabolism

Question 53

The most problematic yet common form of tertiary treatment of water is

A) chlorine
B) UV light
C) ozone
D) X-rays