Ch. 7 Key Terms

Question 1

wetland

Answer 1

an area of land that is periodically underwater or whose soil contains a great deal of moisture.

Question 2

plankton

Answer 2

the mass of mostly microscopic organisms that float or drift freely in the waters of aquatic environments.

Question 3

nekton

Answer 3

all organisms that swim actively in open water, independent of currents.

Question 4

benthos

Answer 4

organisms that live at the bottom of oceans or bodies of freshwater.

Question 5

littoral zone

Answer 5

a shallow zone in a freshwater habitat where light reaches the bottom and nurtures plants.

Question 6

benthic zone

Answer 6

the bottom of oceans or bodies of freshwater.

Question 7

eutrophication

Answer 7

an increase in the number of nutrients, such as nitrates, in a marine or aquatic ecosystem.

Question 8

estuary

Answer 8

an area where freshwater from rivers mixes with salt water from the ocean; the part of a river where the tides meet the river current.

Question 9

salt marsh

Answer 9

a maritime habitat characterized by grasses, sedges, and other plants that have adapted to continual, periodic flooding; salt marshes are found primarily throughout the temperate and subarctic regions.

Question 10

mangrove swamp

Answer 10

a tropical or subtropical marine swamp that is characterized by the abundance of low to tall trees, especially mangrove trees.

Question 11

barrier island

Answer 11

a long ridge of sand or narrow island that lies parallel to the shore.

Question 12

coral reef

Answer 12

a limestone ridge found in tropical climates and composed of coral fragments that are deposited around organic remains.