Deck 25: Aquatic Ecosystems

Question 1

A relatively ________ lake is characterized by an abundance of nutrients,abundant algal growth,and shallow light penetration.

Answer 1

eutrophic

Question 2

Non-flowing water ecosystems,such as ponds and lakes,are also called ________ ecosystems.

Answer 2

lentic

Question 3

In lakes and ponds,the depth at which respiration balances photosynthesis is referred to as the ________ depth of light.

Answer 3

compensation

Question 4

In lakes and ponds,the ________ zone is a shallow-water zone along the perimeter in which light reaches the bottom.

Question 5

The zone in the ocean from the surface to approximately 200 meters deep is called the ________ zone.

Question 6

Classification of aquatic ecosystems is largely based on features of the ________ environment.

Question 7

A(n)________ is a ring of coral reefs and islands surrounding a lagoon that is formed when a volcanic mountain subsides beneath the surface.

Question 8

Invertebrates that feed on the algal coating of stones and rubble in streams and rivers are referred to as ________.

Question 9

In the benthic zone of lakes and ponds,organisms that are attached to or move on a submerged substrate but do not penetrate it are referred to as ________.

Question 10

The tiny,photosynthetic,primary producers of open water such as desmids,diatoms,and filamentous algae are referred to as ________.

Question 11

Lakes that receive large amounts of organic matter from surrounding land,particularly in the form of humic materials that stain the water brown,are called ________ lakes.

Question 12

Flowing-water ecosystems often alternate two different but related habitats: the turbulent ________ and the quiet pool.

Question 13

Smaller than diatoms,the ________,which include tiny cyanobaceteria,haptophtyes,and coccolithophores,make up the largest biomass in temperate and tropical water.

Question 14

Streams generally have a(n)________ temperature at their headwaters than toward their outlet.

Question 15

When rivers flow into the ocean,they create a zone that mixes freshwater with saltwater referred to as a(n)________.

Question 16

________ fish are those that live most of their lives in marine environments and return to freshwater to spawn.

Question 17

The general term for flowing bodies of freshwater is ________.

Question 18

The water above the continental shelf belongs to the ________ province of the pelagic zone.

Question 19

Reef-building corals have a symbiotic relationship with algal cells called ________ that live within the cells of corals.

Question 20

In lakes and ponds,the open-water zone extending to the depth of light penetration is referred to as the ________ zone.

Question 21

Which of the following lakes is likely to be the most oligotrophic?

A)small and shallow
B)small and deep
C)large and shallow
D)large and deep

Question 22

The organisms living on the bottom of the ocean are collectively referred to as

A)nekton.
B)benthos.
C)meiofauna.
D)epifauna.

Question 23

________ are mountainous lakes that have been carved by glacial erosion and deposition.

A)Marshes
B)Oxbows
C)Reservoirs
D)Tarns

Question 24

In lakes and ponds,phytoplankton and zooplankton are most abundant in the

A)benthic zone.
B)littoral zone.
C)limnetic zone.
D)profundal zone.

Question 25

As a stream or river descends,it generally grows

A)faster and cooler.
B)slower and warmer.
C)faster and warmer.
D)slower and cooler.

Question 26

The dominant autotrophs of the open water are

A)phytoplankton.
B)kelp.
C)seagrasses.
D)stromatolites.

Question 27

Shredders,collectors,and small predatory fish such as sculpins,darters,and trout are the dominant organisms collectively found in

A)estuaries.
B)small headwater streams.
C)medium-sized streams.
D)large rivers.

Question 28

In the ocean,swimming organisms that can move at will in the water column are referred to as

A)periphyton.
B)zooplankton.
C)megaplankton.
D)nekton.

Question 29

Many physical features dictate life in an estuary.The physical feature with the most influence on organismal distribution is

A)light.
B)nutrients.
C)salinity.
D)temperature.

Question 30

Which of the following bodies of water best represents a lotic ecosystem?

A)salt pond
B)marsh
C)oxbow lake
D)stream

Question 31

In ponds and lakes,the zone beneath the depth of effective light penetration but above the bottom is referred to as the

A)littoral zone.
B)limnetic zone.
C)profundal zone.
D)benthic zone.

Question 32

Semi-enclosed areas of the coastal ocean where seawater is diluted and partially mixed with freshwater coming from the land are referred to as

A)eddies.
B)coastal reservoirs.
C)tidal basins.
D)estuaries.

Question 33

The benthic community of an ocean,with the exception of hydrothermal vents,is best described as

A)completely heterotrophic and very diverse.
B)completely autotrophic and very diverse.
C)completely phototrophic and not very diverse.
D)mostly heterotrophic and not very diverse.

Question 34

In lakes and ponds,decomposition occurs primarily in the

A)benthic zone.
B)littoral zone.
C)limnetic zone.
D)profundal zone.

Question 35

In lakes and ponds,oxygen concentrations are lowest in the

A)benthic zone.
B)littoral zone.
C)limnetic zone.
D)profundal zone.

Question 36

Streams are classified according to orders.If two first order streams join,flow through a valley,and are joined by another first order stream,what is the final stream order?

A)first order
B)second order
C)third order
D)fourth order

Question 37

In streams and rivers,decomposition occurs primarily in

A)riffles.
B)pools.
C)runs.
D)rapids

Question 38

The oxygen-minimum layer of an ocean occurs in the

A)abyssalpelagic zone.
B)bathypelagic zone.
C)epipelagic zone.
D)mesopelagic zone.

Question 39

Invertebrates that feed on coarse particulate organic matter (CPOM),such as leaves that fall into streams and rivers,are referred to as

A)shredders.
B)gougers.
C)grazers.
D)collectors.

Question 40

In lakes and ponds,photosynthesis occurs primarily in the

A)benthic zone.
B)profundal zone.
C)limnetic zone.
D)lotic zone.

Question 41

The deepest water of an ocean in deep-sea trenches and canyons is referred to as the hadalpelagic zone.

Question 42

Photosynthesis in the ocean takes place mostly in the mesopelagic zone.

Question 43

In rivers and streams,the invertebrates that scrape algae off rocks are referred to as shredders.

Question 44

As a stream flows down its course,it generally becomes warmer and slower.

Question 45

Non-flowing water bodies,such as lakes,are referred to as lotic ecosystems.

Question 46

Phytoplankton thrive in the limnetic zone of lakes and ponds.

Question 47

Unlike phytoplankton,which are at the mercy of currents,zooplankton can move at will within a current.

Question 48

Oxygen concentrations are relatively high in the bottom ooze of lakes and ponds.

Question 49

Swimming organisms in the ocean that are able to move at will in the water column are referred to as nekton.

Question 50

Lakes can be formed from both geological and nongeological activity.

Question 51

The productivity of oceans is greatest in the

A)neritic province at tropical latitudes.
B)oceanic province at tropical latitudes.
C)neritic province at temperate latitudes.
D)oceanic province at temperate latitudes.

Question 52

Eutrophic lakes are typically clear,with little algal growth.

Question 53

Coral reefs grow best where water is

A)warm,shallow,and clear.
B)warm,deep,and clear.
C)cold,shallow,and clear.
D)cold,deep,and murky.

Question 54

Inflowing river waters most often impoverish rather than fertilize estuaries.

Question 55

Most estuarine organisms are benthic.

Question 56

If a stream has an average depth of 3 meters,an average width of 4 meters,and an average stream velocity of 0.25 m/s,what is the discharge rate or streamflow (Q)?

A)0)187 m3/s
B)3 m3/s
C)12 m3/s
D)48 m3/s

Question 57

The cells of reef-building corals are inhabited by symbiotic species of

A)algae.
B)fungi.
C)bacteria.
D)cyanobacteria.

Question 58

Many zooplankton migrate to the surface to graze on phytoplankton during the day and retreat to deeper water during the night.

Question 59

In the profundal zone of a lake or pond,the rate of photosynthesis exceeds the rate of respiration.

Question 60

In hydrothermal vent communities,autotrophic organisms obtain energy by oxidizing

A)reduced sulfur compounds.
B)carbon dioxide.
C)sodium chloride.
D)metals such as copper and iron.

Question 61

Barrier reefs are separated from land by shallow lagoons.

Question 62

Coral reefs occur in nutrient-poor areas of the ocean.

Question 63

Organisms living in deep-sea hydrothermal vents do not need light to obtain their energy.

Question 64

The Colorado River in western North America is so overused that it disappears before it reaches the mouth of the Gulf of California.

Question 65

Because the thermocline is permanent in tropical oceans,little vertical mixing occurs,resulting in low productivity.

Question 66

The organisms responsible for the majority of primary production in marine environments are the copepods.

Question 67

The velocity of water in a stream channel is greater along the margins of the channel than in the center of the channel.

Question 68

Bioluminescence reaches its greatest development in the mesopelagic zone of an ocean.

Question 69

Because of the high pressure and cold temperatures,few species of organisms survive in the deep benthic zone of the ocean.