Exam 28: Microorganisms in Marine and Freshwater Ecosystems

In streams and rivers, most of the microbial biomass is

Which of the following keep the lakes of the East Antarctic Ice Sheet in a liquid state?

The final carbon-nitrogen-phosphorus ratio of the phytoplankton is called the _______ ratio.

The epilimnion of a lake is located below the hypolimnion.

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

Viruses in the marine environment (virioplankton) are very abundant.

Estuaries feature a characteristic salinity profile called a(n) _________ _________ .

Microbes within glaciers are

The oceans contain about ____ percent of the earth's water.

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

What fraction of all of the organic carbon on earth results from microbial fixation of carbon dioxide in the oceans?

Much of the loss of biologically available nitrogen in the ocean is now thought to be due to a consortium of microbes carrying out

In the ocean, organic matter sinks from the surface to great depths as

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

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

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

Cyanobacteria such as Synechococcus and Prochlorococcus are predominate members of the phytoplankton in illuminated surface waters.

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

Growth in ocean areas that are high nutrient and low chlorophyll (HNLC) is limited by the availability of

If phosphorus is added to water that contains no other major nutrients, the major microbial group that will bloom if the water is exposed to light will be the