Question 1

When direct examination of virioplankton is carried out by transmission electron microscopy, the numbers obtained are reported as

Accepted Answer

A)  plaque-forming units 
B)  virus-like particles 
C)  viral potential 
D)  particulate organic matter

Question 2

Marine microbes inhabit sediments on the ocean floor at a depth of up to at least

Accepted Answer

A)  one foot. 
B)  ten feet 
C)  100 feet 
D)  0.6 kilometers

Question 3

The open ocean is a(n) _____________ environment.

Accepted Answer

A)  eutrophic 
B)  oligotrophic 
C)  neotrophic 
D)  phylotrophic

Question 4

Barophilic bacteria

Accepted Answer

A)  tolerate high concentration of barium. 
B)  grow at pressures up to 1,100 atm. 
C)  grow only in environments of reduced atmospheric pressure, such as found at high elevation. 
D)  require high concentrations of H2S gas for growth.

Question 5

Salt marshes differ from estuaries in that the freshwater input in salt marshes is from a single source.

Accepted Answer

A) True 
 B)False

Question 6

The buffering effect of the balance between carbon dioxide, bicarbonate, and carbonate is stronger in freshwater than it is in the marine environment.

Accepted Answer

A) True 
 B)False

Question 7

Water ecosystems become eutrophic when there is

Accepted Answer

A)  nutrient enrichment of waters. 
B)  nutrient removal from waters. 
C)  acidification of waters. 
D)  deoxygenation of waters.

Question 8

The discharge of high levels of microbial nutrients into marine environments has

Accepted Answer

A)  resulted in the production of large hypoxic or anoxic regions. 
B)  had negative impacts on shellfish and other bottom-dwelling marine animals. 
C)  resulted in algal blooms and red tides that have killed marine mammals. 
D)  all of the choices

Question 9

The largest fraction of saltwater is that which is frozen at the Earth's polar regions.

Accepted Answer

A) True 
 B)False

Question 10

The importance of phage-mediated lateral gene transfer by virioplankton was illustrated by the fact that cyanophages thought to infect Synechococcus and Prochlorococcus carry the structural gene for

Accepted Answer

A)  nitrogenase. 
B)  phycocyanin production. 
C)  a photosynthetic reaction center protein. 
D)  all of the choices

Question 11

Among the eukaryotic microbes in the phytoplankton, the ________ are most noted for their contribution to carbon fixation.

Accepted Answer

A)  dinoflagellates 
B)  green algae 
C)  diatoms 
D)  cyanobacteria

Question 12

Thiomargarita species store large amounts of ____________ in huge internal vacuoles.

Accepted Answer

A)  nitrate 
B)  sulfate 
C)  oxygen 
D)  hydrogen sulfide

Question 13

Winogradsky columns

Accepted Answer

A)  are typically used to isolate aquatic protozoa. 
B)  are used as a model system for studying microbial interactions. 
C)  are used in the process of isolating nanobacteria. 
D)  are used in the process of isolating aquatic viruses (virioplankton).

Question 14

Methane hydrates found at the bottom of the ocean

Accepted Answer

A)  vastly exceed in amount the world's current known natural gas reserves. 
B)  float to the surface where they are consumed by methylotrophs. 
C)  are only formed in areas of thermal heating. 
D)  all of the choices

Question 15

The biologically available carbon that is produced within large, lentic rivers and lakes is called ___________.

Accepted Answer

The answer of The biologically available carbon that is produced...

Question 16

The solubility of oxygen in water will change in which way when the water temperature is lowered?

Accepted Answer

A)  No change will occur. 
B)  The solubility will increase. 
C)  The solubility will decrease. 
D)  The solubility will first decrease then increase.

Question 17

Competitive advantages for cyanobacteria in the aquatic environment include

Accepted Answer

A)  the ability of many to fix nitrogen. 
B)  the production of toxins to resist predation. 
C)  the production of hydroxamates to bind iron. 
D)  all of the choices

Question 18

In which of the following types of waters do seasonal climatic temperature changes result in distinct chemical and microbial stratification?

Accepted Answer

A)  oceans 
B)  lakes in temperate areas 
C)  lakes in tropical areas 
D)  fast flowing rivers

Question 19

Which of the following statements concerning the microbial loop is not true?

Accepted Answer

A)  microbes consume dissolved organic matter 
B)  marine viruses contribute to the production of dissolved organic matter 
C)  microbes constitute particulate organic matter for zooplankton consumption 
D)  all of the statements are true

Question 20

The chemolithotrophs that metabolize reduced sulfur compounds using oxygen as a terminal electron acceptor in the Winogradsky column include

Accepted Answer

A)  Desulfovibrio. 
B)  Beggiatoa. 
C)  Chromatium. 
D)  cyanobacteria.

Exam 28: Microorganisms in Marine and Freshwater Ecosystems

When direct examination of virioplankton is carried out by transmission electron microscopy, the numbers obtained are reported as

Marine microbes inhabit sediments on the ocean floor at a depth of up to at least

The open ocean is a(n) _____________ environment.

Barophilic bacteria

Salt marshes differ from estuaries in that the freshwater input in salt marshes is from a single source.

The buffering effect of the balance between carbon dioxide, bicarbonate, and carbonate is stronger in freshwater than it is in the marine environment.

Water ecosystems become eutrophic when there is

The discharge of high levels of microbial nutrients into marine environments has

The largest fraction of saltwater is that which is frozen at the Earth's polar regions.

The importance of phage-mediated lateral gene transfer by virioplankton was illustrated by the fact that cyanophages thought to infect Synechococcus and Prochlorococcus carry the structural gene for

Among the eukaryotic microbes in the phytoplankton, the ________ are most noted for their contribution to carbon fixation.

Thiomargarita species store large amounts of ____________ in huge internal vacuoles.

Winogradsky columns

Methane hydrates found at the bottom of the ocean

The biologically available carbon that is produced within large, lentic rivers and lakes is called ___________.

The solubility of oxygen in water will change in which way when the water temperature is lowered?

Competitive advantages for cyanobacteria in the aquatic environment include

In which of the following types of waters do seasonal climatic temperature changes result in distinct chemical and microbial stratification?

Which of the following statements concerning the microbial loop is not true?

The chemolithotrophs that metabolize reduced sulfur compounds using oxygen as a terminal electron acceptor in the Winogradsky column include