Exam 30: Microorganisms in Marine and Freshwater Ecosystems

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

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

The epilimnion of a lake is located below the hypolimnion.

The cyanobacterium Trichodesmium ______.

Competitive advantages for cyanobacteria in the aquatic environment include ______.

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 ______.

Microbes within glaciers are ______.

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

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

Methane hydrates found at the bottom of the ocean ______.

In general,cyanobacteria prefer higher pH and temperature conditions than algae.

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

Water ecosystems become eutrophic when there is ______.

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

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

A potent neurotoxin that causes paralytic shellfish poisoning in coastal temperate North America is produced by ______.

In the open ocean,_______.

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

In streams and rivers,most of the microbial biomass is _______.

Silicobacter pomeroyi produces carbon monoxide dehydrogenases so that it can use carbon monoxide as a source of carbon.