Question 1

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 2

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 3

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

Accepted Answer

A) True 
 B)False

Question 4

SAR11 bacteria are now thought to constitute about _____ percent of all microbial life on earth.

Accepted Answer

A) five 
B) ten 
C) twenty five 
D) forty

Question 5

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 6

The initial degradation of cellulose that initiates microbial growth in the Winogradsky column is carried out by

Accepted Answer

A) Clostridium. 
B) Desulfovibrio. 
C) cyanobacteria. 
D) Rhodopseudomonas.

Question 7

The possible effect of failing to limit greenhouse gas emissions on the oceans is likely to be which of the following?

Accepted Answer

A) An increase in dissolved methane will stimulate microbial growth. 
B) An increase in dissolved methane will hinder microbial growth. 
C) An increase in dissolved carbon dioxide will lower the pH. 
D) An increase in dissolved carbon dioxide will raise the pH.

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 open ocean is a(n)_____________ environment.

Accepted Answer

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

Question 10

In streams and rivers,most of the microbial biomass is

Accepted Answer

A) floating on the surface. 
B) buried in bottom sediments. 
C) attached to surfaces. 
D) metabolically inactive.

Question 11

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 12

The process in which diurnal oxygen shifts can occur in a river after organic matter is added is called

Accepted Answer

A) self-reduction. 
B) self-purification. 
C) self-oxidation. 
D) self-eutrophication.

Question 13

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.

Question 14

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 15

A potent neurotoxin that causes paralytic shellfish poisoning in coastal temperate North America are produced by

Accepted Answer

A) diatoms. 
B) red algae. 
C) green algae. 
D) dinoflagellates.

Question 16

The genome of Pelagibacter ubique

Accepted Answer

A) is the smallest one thus far sequenced for a non-parasitic bacterium. 
B) contains no pseudogenes. 
C) has a very limited number of nucleotides between coding regions. 
D) all of the choices.

Question 17

Most microbes that inhabit estuaries are

Accepted Answer

A) halophilic. 
B) halotolerant. 
C) halophobic. 
D) halovariable.

Question 18

The depth to which light penetrates with sufficient intensity to support the activities of photoautotrophic organisms in the ocean is called the __________ zone.

Accepted Answer

The answer of The depth to which light penetrates with...

Question 19

Low-nutrient,oligotrophic waters will usually become stratified and have an anaerobic hypolimnion at certain times of the year.

Accepted Answer

A) True 
 B)False

Question 20

The epilimnion of a lake is located below the hypolimnion.

Accepted Answer

A) True 
 B)False

Exam 30: Microorganisms in Marine and Freshwater Ecosystems

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

Methane hydrates found at the bottom of the ocean

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

SAR11 bacteria are now thought to constitute about _____ percent of all microbial life on earth.

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

The initial degradation of cellulose that initiates microbial growth in the Winogradsky column is carried out by

The possible effect of failing to limit greenhouse gas emissions on the oceans is likely to be which of the following?

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

The open ocean is a(n) _____________ environment.

In streams and rivers,most of the microbial biomass is

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

The process in which diurnal oxygen shifts can occur in a river after organic matter is added is called

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

Competitive advantages for cyanobacteria in the aquatic environment include

A potent neurotoxin that causes paralytic shellfish poisoning in coastal temperate North America are produced by

The genome of Pelagibacter ubique

Most microbes that inhabit estuaries are

The depth to which light penetrates with sufficient intensity to support the activities of photoautotrophic organisms in the ocean is called the __________ zone.

Low-nutrient,oligotrophic waters will usually become stratified and have an anaerobic hypolimnion at certain times of the year.

The epilimnion of a lake is located below the hypolimnion.