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