Deck 23: Major Microbial Habitats and Diversity

Question 1

Which are the MOST dominant chemolithotrophs in pelagic waters?

A) ammonia- oxidizing Archaea
B) ammonia- oxidizing Bacteria
C) Prochlorococcus
D) sulfate- reducing Bacteria

Answer 1

A

Question 2

Which statement is TRUE about the fluid from the hydrothermal vents?

A) The fluid usually contains about equal amounts of organic and inorganic material.
B) The fluid contains large amounts of oxidized inorganic materials.
C) The fluid contains large amounts of organic material.
D) The fluid contains large amounts of reduced inorganic materials.

Answer 2

D

Question 3

Which metabolic strategy is most common in chemolithotrophic mats?

A) iron oxidation
B) nitrate reduction
C) sulfur oxidation
D) ammonia oxidation

Answer 3

C

Question 4

Which of the following can function as intracellular signaling molecules?

A) hydrophilic lipids
B) acylated homoserine lactones
C) proteorhodopsins
D) quinones

Question 5

To observe specific microorganisms in a soil particle, one can use

A) fluorescent antibody staining.
B) FISH.
C) scanning electron microscopy.
D) all of the above.

Question 6

In a stratified lake, the warmer and less dense layer is called the

A) epilimnion.
B) thermocline.
C) hyperlimnion.
D) hypolimnion.

Question 7

Which chlorophylls do prochlorophytes contain?

A) a and d
B) a and b
C) a and c
D) a and b, or a and d

Question 8

An organism living in the bottommost region of a body of water is described as being

A) litoral.
B) neritic.
C) benthic.
D) pelagic.

Question 9

Which is the CORRECT order of increasing size in soil particles?

A) clay > silt > sand
B) sand > clay > silt
C) silt > clay > sand
D) clay > sand > silt

Question 10

Which metric describes the total number of species present in a community?

A) species evenness
B) species richness
C) species abundance
D) species diversity

Question 11

The chemical oxygen demand (COD) of a body of water is determined using a(n)

A) strong oxidizing agent.
B) spectrophotometer to determine the OD540nm.
C) oxygenator.
D) microelectrode.

Question 12

Assuming exposure to the same climate, which of the following aquatic systems would be MOST stratified?

A) 200 m deep saltwater lake
B) 50 m deep marine water fjord
C) 300 m deep freshwater lake
D) 20 m deep freshwater river

Question 13

Microorganisms in the laboratory generally grow when compared to their growth in the environment.

A) for a longer period of time
B) at about the same rate
C) faster
D) slower

Question 14

The primary metal sulfides emitted from the black smokers are sulfides.

A) magnesium
B) copper
C) zinc
D) iron

Question 15

Most Archaea identified in deep- sea sediments are

A) Thaumarchaeota.
B) Nanoarchaeota.
C) Euryarchaeota.
D) Crenarchaeota.

Question 16

Archaea in pelagic deep- water are almost exclusively

A) Euryarchaeota.
B) Crenarchaeota.
C) Nanoarchaeota.
D) Thaumarchaeota.

Question 17

Microenvironments of soil exist where concentrations greatly vary.

A) oxygen
B) sulfur
C) nitrate
D) all of the above

Question 18

Shallow marine sediments are dominated by

A) Tenericutes.
B) Planctomycetes.
C) Proteobacteria.
D) Firmicutes.

Question 19

Soils derived from rock weathering are called _ _ soils.

A) nutrient
B) inorganic
C) mineral
D) organic

Question 20

The abundance of cyanobacterial mats has greatly declined due to the evolution of

A) antimicrobial- producing fungi.
B) bacteriophages.
C) Proteobacteria.
D) metazoan grazers.

Question 21

A soil that lacks a dominate particle size is referred to as a(n)

A) bisequum.
B) loam.
C) mottled soil.
D) aggregation.

Question 22

Ecological theory states that for every organism there is at least one _, and the microenvironment where the organism is most successful is called the .

Question 23

Water in the rocks and soils of Earth's subsurface is called _.

Question 24

According to bacterial abundance studies done so far on soils, the are generally not in high numbers when compared to other bacterial classes within the Proteobacteria phylum.

A) Deltaproteobacteria
B) Gammaproteobacteria
C) Epsilonproteobacteria
D) Alphaproteobacteria

Question 25

The microbial oxygen- consuming capacity of a water sample is called its .

Question 26

What adaptation do organisms have that tolerate high pressures?

A) decreased lipid content
B) decreased cell size
C) increased ribosome size
D) increased unsaturated fatty acids

Question 27

Cyclic dimeric guanosine monophosphate (c- di- GMP) serves as a messenger molecule in bacterial cells to coordinate a shift from _ to _ growth.

Question 28

What is an average concentration of prokaryotic cells along the surface of pelagic water?

A) 108 cells/ml
B) 104 cells/ml
C) 1010 cells/ml
D) 106 cells/ml

Question 29

The deep sea is defined as marine water below a depth of

A) 100 m.
B) 5 km.
C) 1 km.
D) 10 km.

Question 30

Biomass generation due to heterotrophic organisms is called production.

Question 31

Cells within a biofilm excrete an adhesive matrix primarily composed of _ but also can contain nucleic acids as well as proteins.

Question 32

A notorious biofilm former, implicated in cystic fibrosis, is

A) Bacillus subtilis.
B) Lactobacillus acidophilus.
C) Pseudomonas aeruginosa.
D) Escherichia coli.

Question 33

In the oceans, prokaryotes are outnumbered ten to one by .

Question 34

From the aquatic systems below, where are heterotrophic Bacteria the MOST abundant?

A) coastal waters
B) open ocean
C) Sargasso Sea
D) deep sea

Question 35

The photosynthetic pigments bacteriorhodopsin and proteorhodopsin are present in and , respectively.

A) Bacteria / Eukarya
B) Bacteria / Bacteria
C) Archaea / Bacteria
D) Bacteria / Archaea

Question 36

Which bacterial genus is responsible for producing ferrous iron (Fe2+) in groundwater?

A) Alteromonas
B) Geobacter
C) Loktanella
D) Aquifex

Question 37

Which aquatic habitat contains a pelagic zone?

A) open ocean
B) salt marsh
C) estuary
D) lake

Question 38

Which of the following is NOT an oxygenic phototrophic microorganism present in marine waters?

A) Trichodesmium
B) Ostreococcus
C) Roseobacter
D) Prochlorococcus

Question 39

The emergence of new microbial species because of geographic isolation is called speciation.

A) biogeological
B) isolatory
C) biogeochemical
D) allopatric

Question 40

Dental plaque is an example of a .

Question 41

An ecosystem includes both the living organisms and abiotic materials that function together.

Question 42

Water is held in soil by _ and between soil particles.

Question 43

Three major environmental extremes of the deep sea are high , low , and low_ _.

Question 44

A chemical that comes from outside the ecosystem is referred to as a(n) chemical.

Question 45

Anaerobic microbes can thrive just millimeters below the air- soil interface.

Question 46

Sedimentation in bogs and marshes develop _ soils.

Question 47

Mineral soils largely come from weathered limestone and sand.

Question 48

The physiochemical conditions of a microenvironment, by definition, remain static.

Question 49

A microbial population can contain several microbial communities.

Question 50

Microbial life has been identified at depths of 3 km despite being anoxic.

Question 51

A population of metabolically related microorganisms is called a(n) .

Question 52

Chemolithotrophic bacteria use released from deep- sea hydrothermal vents.

Question 53

Soil particles are classified based on their size.

Question 54

The cells within a biofilm can undergo intraspecies signaling, however interspecies signaling does not occur.

Question 55

Sudden nutrient perturbations in an environment generally the overall prokaryotic diversity.

Question 56

In the context of nutrients, a sink is one that slowly releases a particular nutrient over time.

Question 57

The activity of primary producers in open marine environments is limited by inorganic nutrient levels, particularly the levels of , , and .

Question 58

The most abundant prokaryotic organism in the ocean is of the genus.

Question 59

Carbon dioxide produced during respiration becomes dissolved in water as _, which dissolves limestone- containing rocks.

Question 60

Functional differences can be observed by using 16S rRNA gene phylogenetics of a microbial community.

Question 61

Chemoorganotrophic bacteria can facilitate the formation of soil through the secretion of organic acids.

Question 62

Unlike other cyanobacteria, Prochlorococcus lacks phycobilins.

Question 63

Limiting nutrients in soils are generally organic compounds.

Question 64

Archaea and Bacteria dominate the upper 100 m of the open ocean while viruses dominate depths greater than 100 m.

Question 65

The formation of soil involves a combination of biological, chemical, and physical processes.

Question 66

All stratified lakes contain a thermocline.

Question 67

Purple phototrophic bacteria that use bacteriochlorophyll a are oxygenic.

Question 68

Provide a reason why using a microelectrode might not reveal the true picture of how much dissolved oxygen is evolving in a microbial community.

Question 69

Describe four environmental conditions that would likely change the relative abundances of the members within a microbial community.

Question 70

Due to nutrient limitation in open ocean waters, certain regions are essentially devoid of microbial life.

Question 71

Low return of nutrients in the pelagic zone results in relatively low primary production in the open ocean when compared to freshwater lake systems.

Question 72

Explain why biofilms are a concern in medicine.

Question 73

Chemical diffusion plays a major role in the availability of chemicals for microorganisms.

Question 74

Describe two roles viruses have in the open ocean.

Question 75

Explain how both biochemical oxygen demand and chemical oxygen demand are measured.

Question 76

Due to such an array of nutrients, microorganisms are often capable of sustaining exponential growth in the environment.

Question 77

Due to microbial heterotrophic activity, even well mixed aquatic systems can have depleted oxygen content when high organic inputs occur.

Question 78

Oligotrophic organisms do not grow well under nutrient replete conditions.

Question 79

Some ecosystems are inhabited exclusively by microorganisms.

Question 80

In many marine systems, the carbon and oxygen cycles are directly proportional to each other.