Chapter 16—Continental Shelves and Neritic Zone
MULTIPLE CHOICE
1. The average width of the continental shelves is
a.
1 mile.
b.
10 miles.
c.
40 miles.
d.
480 miles.
e.
4800 miles.
2. Productivity in coastal waters is high due to
a.
nutrients from land.
b.
sediments rich in nutrients.
c.
upwelling.
d.
both a and c
e.
a, b, and c.
3. Food for the continental shelf benthic community primarily comes in the form of
a.
migratory fish.
b.
living kelps.
c.
detritus.
d.
plankton.
e.
nutrients from terrestrial runoff.
4. The benthic areas of continental shelf regions are dependent upon ____ for food.
a.
phytoplankton
b.
zooplankton
c.
sinking detritus
d.
attached algae
e.
epifauna
5. All the following utilize detritus for food except
a.
filter-feeders.
b.
grazers.
c.
suspension-feeders.
d.
detritus-feeders.
6. Even though coastal areas comprise only 10% of the oceans’ area, they make up ____% of the total
oceans’ fisheries.
a.
10
b.
20
c.
60
d.
90
e.
50
7. In areas of the continental shelf where bottom currents are weak, the environment is considered to be
a.
harsh.
b.
always changing.
c.
generally stable.
d.
cyclically fluctuating.
e.
low in species diversity.
8. Filter feeders on coastal shelves tend to dominate in areas that have:
a.
moving currents and coarse sediments.
b.
no currents and fine sediments.
c.
silty areas.
d.
muddy areas.
9. Coarse sediment bottoms primarily support
a.
infauna.
b.
interstitial animals.
c.
epifauna.
d.
pelagic organisms.
e.
seaweeds.
10. In soft-bottom communities suspension feeders dominate
a.
where sediments are generally muddy.
b.
as infauna.
c.
where sediments are generally sandy.
d.
as meiofauna.
11. Burrowing deposit feeders favor ____ bottoms.
a.
muddy
b.
rocky
c.
sandy
d.
cobble
e.
pebble
12. Fine sediment bottoms with silt support a variety of
a.
filter feeders.
b.
suspension feeders.
c.
epifauna.
d.
infauna.
e.
nekton.
13. In soft-bottom communities deposit feeders dominate
a.
where sediments are generally muddy.
b.
as epifauna on worm tubes.
c.
as meiofauna.
d.
where sediments are generally sandy.
e.
where oxygen levels are low.
14. The interaction of suspension and deposit feeders in muddy areas
a.
is an example of mutualism.
b.
is an example of interference when sediment particles from deposit feeders’ activity clogs
suspension feeders’ ability to feed and exchanges gases.
c.
demonstrates that deposit feeders can outcompete suspension feeders.
d.
demonstrates that suspension feeders outcompete deposit feeders.
e.
is an example of a keystone predator.
15. Communities on hard substrate are often found distributed
a.
randomly.
b.
equally spaced out.
c.
equally spaced along a vertical gradient.
d.
in patches.
16. Patchiness of the soft-bottom benthos is a result of:
a.
uneven distribution of food.
b.
uneven distribution of sediments on the bottom.
c.
low concentrations of nutrients on the bottom.
d.
uneven distribution of predators.
17. Changes in sediment distribution can be attributed to all except:
a.
currents.
b.
burrowing animals.
c.
feeding activity of predators.
d.
temperature – salinity shifts.
18. The pattern of larval settlement depends on all except:
a.
light levels.
b.
currents.
c.
predation.
d.
type of bottom substrate.
19. Larger baleen whales feed on:
a.
demersal fish.
b.
krill.
c.
suspension feeders.
d.
sea stars.
e.
other marine mammals.
20. In the neritic zone, a 10-milliliter sample of surface water can contain ____ of multicellular planktonic
organisms.
a.
hundreds
b.
thousands
c.
millions
d.
billions
e.
trillions
21. Microphytoplankton is:
a.
2.0 to 20 microns.
b.
20 – 200 microns.
c.
0.2 – 20 mm.
d.
20 – 200 cm.
e.
20 – 200 mm.
22. Nanophytoplankton is
a.
2.0 to 20 microns.
b.
20 – 200 microns.
c.
2 – 20 mm.
d.
20 – 200 cm.
e.
20 – 200 mm.
23. Coccolithophores are abundant in:
a.
cold marine waters.
b.
tropical waters.
c.
subtropical areas.
d.
open ocean.
e.
river mouths and estuaries.
24. Which of these is an often abundant plankton organism in the North Sea?
a.
Radiolarians
b.
Shrimp
c.
Coccolithophores
d.
Dinoflagellates
e.
Ocean sunfish (Mola mola)
25. Diatoms tend to be grazed in temperate coastal waters by:
a.
amphipods.
b.
dinoflagellates.
c.
copepods.
d.
lobsters.
e.
radiolarians
26. In warm and temperate waters, common phytoplankton are the
a.
diatoms.
b.
radiolarians.
c.
coccolithophores.
d.
dinoflagellates.
e.
salps.
27. During high productive periods copepod abundance can be as high as:
a.
100 individuals per cubic meter.
b.
1,000 individuals per cubic meter.
c.
10,000 individuals per cubic meter.
d.
100,000 individuals per cubic meter.
e.
1,000,000 individuals per cubic meter.
28. The number of trophic levels between primary producers and large consumers in coastal waters is
usually:
a.
one.
b.
two.
c.
three.
d.
four.
e.
more than four.
29. The high productivity and short food chains of ____ areas support the greatest biomass of any
planktonic system.
a.
stable water column
b.
turbid
c.
upwelling
d.
downwelling
e.
coral reef.
30. About 50% of the world’s commercial fish supply comes from areas of:
a.
deep submarine canyons.
b.
atolls.
c.
benthic outer-edge of the continental shelf.
d.
upwelling.
e.
mid-ocean ridges.
31. Many benthic organisms are dependent upon the neritic area to:
a.
complete their life history cycle with juveniles as part of the plankton.
b.
provide plankton for food.
c.
protect them from desiccation and UV radiation.
d.
both a and b
32. Kelps cannot live in water warmer than ____° C.
a.
10
b.
20
c.
30
d.
40
e.
50
33. Laminaria is the genus of kelp that dominates in:
a.
the Pacific coast.
b.
the South Atlantic.
c.
the Tropical Pacific.
d.
the North Atlantic.
e.
the Indian Ocean.
34. Macrocystis is the genus of kelp that dominates in:
a.
the Indian Ocean.
b.
the North Atlantic.
c.
the Tropical Pacific.
d.
the Mediterranean.
e.
the Pacific Ocean.
35. Macrocystis can grow up to ____ centimeters per day.
a.
10
b.
15
c.
35
d.
50
e.
100
36. Macrocystis kelp communities have numerous ____ organisms while Laminaria kelp communities
have ____ organisms.
a.
swimming, crawling
b.
crawling, swimming
c.
benthic, pelagic
d.
pelagic, benthic
e.
benthic, crawling
37. An important grazer of kelp plants is the:
a.
octopus.
b.
kelp bass.
c.
sea urchin.
d.
sea otter.
e.
sea anemone.
38. Kelps require ____ substrates in order to grow.
a.
rocky
b.
muddy
c.
silty
d.
sandy
e.
porous
39. Kelp beds are considered important because they support large
a.
fish.
b.
sea urchins.
c.
diverse communities.
d.
sea otters.
e.
sharks.
40. One commercially important species that is a resident of kelp forests is the
a.
abalone.
b.
mussel.
c.
cowrie.
d.
lobster.
e.
sea anemone.
41. A gribble:
a.
is the substrate required for kelp to grow on.
b.
is a snail that crawls along kelp stipes.
c.
is a group of lobsters.
d.
is a crustacean that burrows into kelp holdfasts.
e.
is an echinoderm that consumes kelp.
42. Gribbles play an important role in kelp communities
a.
by weakening holdfasts enabling kelps to be replaced.
b.
by strengthening holdfasts enabling kelps to remain attached.
c.
by randomly disturbing the environment.
d.
by providing substrate for kelp undercover species.
e.
by acting as keystone predators.
43. On the west coast of North America, sea urchins were historically kept in check by:
a.
lobsters.
b.
surf perches.
c.
sea otters.
d.
crabs.
e.
SCUBA divers.
TRUE/FALSE
44. Kelps of the genus Macrocystis are perennials.
45. Coastal waters are highly productive areas.
46. Filter feeders are common in kelp forests.
47. One square meter of open ocean areas supports more phytoplankton growth than a comparable coastal
water area.
48. The type of sediment limits the kinds of organisms that can live in a particular area.
49. Diatoms dominate coastal waters of tropical and subtropical areas.
50. Dinoflagellates tend to dominate in warmer waters.
51. Kelps are a major source of detritus to kelp forest dwellers.
242 Chapter 16—Continental Shelves and Neritic Zone
52. The delicate nature of kelp beds is a result of the slow growth rates of kelps.
53. Sea urchin populations are not affected by the decimation of kelp forests because these animals are
generalists and can switch their diets.
MATCHING
Match the words with the most closely associated term.
a.
live in spaces between sediment particles
b.
live on the surface sediments
c.
burrow in the sediments
54. Infauna
55. Interstitial
56. Epifauna
Match a common ocean location with its most closely associated species.
a.
Pacific coast
b.
Pacific and southern Atlantic
c.
North Atlantic temperate
57. the giant kelp Macrocystis
58. the brown alga Laminaria
59. the abalone Haliotis
Match the words with the most closely associated term.
a.
slender stalk
b.
attached to rocks
c.
leaf-like blades
60. Holdfast
61. Stipe
62. Fronds
Match the words with the most closely associated organism.
a.
feed on other molluscs
b.
damage kelp by burrowing into holdfast
243 Chapter 16—Continental Shelves and Neritic Zone
c.
builds fecal mounds
63. Gribbles
64. Sea cucumber
65. Whelks
Match the trophic role with a closely associated kelp community species.
a.
rockfish
b.
kelp
c.
gribble
66. Primary producer
67. Primary consumer
68. Secondary consumer
Match the consumer with its typical mode of feeding.
a.
eats detritus and bacteria
b.
scavenger and predator
c.
eats detritus and plankton
d.
herbivore
69. Suspension feeder
70. Deposit feeder
71. Sunflower star
72. Sea urchin Strongylocentrotus
Match the substrate type with the most closely associated organisms.
a.
sandy bottom
b.
muddy bottom
c.
hard bottom
73. Epibenthic
74. Suspension
75. Burrowing
ESSAY
76. Briefly describe the ecological importance of coastal seas.
77. What is the main source of nutrition for animals that live on the continental shelf?
78. How do kelp beds in the northeastern U.S. differ from those of the northwestern U.S.? What is the
dominant non-human predator in each habitat?
79. Describe 3 adaptations of benthic fishes for living on the continental shelf.
80. In any ecosystem, short food chains are more efficient than longer ones. Why is this so?
245 Chapter 16—Continental Shelves and Neritic Zone
81. Compared to oceanic waters, coastal waters are much more productive areas. Describe at least 3
factors that contribute to the high productivity of these waters.
82. Briefly describe the ecology and trophic abundance of the Southern Ocean.
83. Describe how population size of lobsters affects the extent of kelp forests on the North Atlantic coast
of North America.