Deck 13: Life on the Continental Shelf

Question 1

The concentration of nutrients in the waters over the continental shelf is typically:

A)Higher than in the open ocean.
B)Lower than in the open ocean.
C)About the same.
D)No generalizations can be made: the amount of nutrients depends on the type of substrate.
E)No generalizations can be made: the amount of nutrients depends on having or not having kelp.

Answer 1

A

Question 2

The higher the water turbulence such as wave action,the higher the relative number of:

A)Planktonic species.
B)Deposit feeders.
C)Nektonic species.
D)Filter feeders.
E)Primary producers.

Answer 2

D

Question 3

One of the following statements best describes the temperature and salinity of the deep water over the continental shelf:

A)It is typically very different from that of the surface as a result of light affecting only the surface.
B)It is usually about the same along the entire water column as a result of the type of sediment.
C)It is usually about the same along the entire water column as a result of currents and wave action.
D)It is typically very different from that of the surface as a result of differences in nutrients.
E)It is typically very different from that of the surface as a result of the higher density of surface water.

Answer 3

C

Question 4

Which of the following is a positive effect of bioturbators?

A)Oxygenate sediments
B)Bury infauna
C)They absorb toxins from the sediments
D)They stabilize the detritus
E)All answers are correct

Question 5

As turbulence decreases:

A)The amount of oxygen in the sediment decreases.
B)The amount of detritus in the sediment decreases.
C)The size of sediment particles increases.
D)The relative number of suspension feeders increases.
E)The relative number of seaweed species increases.

Question 6

Which of the following factors is most likely to have an effect on the global distribution of organisms on the continental shelf?

A)Stratification of water
B)Oxygen
C)Nutrients
D)Temperature
E)Turbulence

Question 7

Typically,the dominant inhabitants of rocky subtidal bottoms in shallow water are:

A)Crabs.
B)Sea urchins.
C)Macroalgaes/Seaweeds.
D)Seagrasses.
E)Sessile worms.

Question 8

The plankton and nekton that inhabit the water column over the continental shelf are said to live in what zone?

A)Neritic zone
B)Shelf break
C)Benthic zone
D)Abyssal zone
E)Hadal zone

Question 9

Most of the biomass produced by seagrasses find their way into the food chain by way of:

A)Small herbivores that eat the plants.
B)Detritus.
C)Epiphytes that live on the surface of leaves and also feed on the plants.
D)Plankton that thrive on nutrients released by the plants.
E)Large herbivores such as manatees and sea turtles that feed on the plants.

Question 10

The region with the largest number of seagrass species is:

A)East Pacific.
B)Atlantic.
C)Indo-West Pacific.
D)Caribbean.
E)Mediterranean.

Question 11

The distribution of the infauna of soft-bottom subtidal communities is often closely related to:

A)Temperature.
B)Particle size of sediment.
C)Salinity.
D)Distribution of seaweeds.
E)Light.

Question 12

The pattern of spatial distribution most often seen in soft-bottom subtidal communities:

A)Regular.
B)Irregular.
C)Random.
D)Clumped.
E)Patchy.

Question 13

Deposit feeders would be most likely to be found on which substrate?

A)Coral reefs
B)Muddy bottoms
C)Gravel bottoms
D)Rocky shores
E)None of the choices are correct

Question 14

Most of the sediment over the continental shelf consists of:

A)Siliceous ooze.
B)Calcareous ooze.
C)Lithogenous.
D)Biogenous.
E)A mixture of siliceous and calcareous ooze.

Question 15

What type of animals are typically absent in soft-bottom subtidal communities:

A)Epifauna.
B)Benthic.
C)Infauna.
D)Sessile.
E)Deposit feeders.

Question 16

One of the following will be relatively uncommon component of rocky subtidal communities due to the nature of the substrate:

A)Producers.
B)Grazers.
C)Predators.
D)Infauna.
E)Epifauna.

Question 17

Settlement and metamorphosis in the planktonic larvae of many subtidal animals is determined or influenced by:

A)Biological factors such as presence of adults.
B)Physical factors such as the type of bottom.
C)Both biological and physical factors.
D)None of the choices are correct.

Question 18

The most important food source in unvegetated soft-bottom subtidal communities:

A)Plankton.
B)Drift seaweeds.
C)Nekton.
D)Benthic prey.
E)Detritus.

Question 19

The part of the continental shelf that is never exposed at low tide is called the:

A)Littoral zone.
B)Subtidal zone.
C)Intertidal zone.
D)Pelagic zone.
E)Abyssal zone.

Question 20

The difference in the tint of the waters above the continental shelf (greenish)and the deep blue of the open ocean is due to:

A)The refraction of light near the coastline.
B)The turbulence of shallow-water wave action.
C)The presence of large numbers of carnivorous fishes.
D)The shallow depth of the continental shelf out to the shelf break.
E)The high level of photosynthetic productivity.

Question 21

Due to the current circulation patterns the distribution of kelps is expected to be the widest on coasts along the:

A)Eastern side of oceans.
B)Western side of oceans.
C)Southern Hemisphere.
D)Northern Hemisphere.
E)Equator.

Question 22

Primary production on soft-bottomed subtidal communities is highest in:

A)Salt marshes.
B)Mangrove forests.
C)Seagrass beds.
D)Oyster reefs.
E)Coral reefs.

Question 23

Which of the following organisms is most likely to be an epiphyte?

A)Algae
B)Seagrass
C)Mangroves
D)Snails
E)Crabs

Question 24

Sea otters are known to affect the development of giant kelp forests by:

A)Helping in the dispersion of spores.
B)Removing competing seaweeds.
C)Feeding on carnivorous fishes.
D)Feeding on grazing sea urchins.
E)Releasing nutrients present in feces and urine.

Question 25

Kelps are characteristic of:

A)Soft bottoms.
B)Arctic and Antarctic coasts.
C)Hard bottoms in the tropics.
D)Soft bottoms but only in the tropics.
E)Temperate regions.

Question 26

By definition,kelp forests develop when:

A)Kelp fronds extend far enough to float on the surface.
B)The kelp is large enough to rise off of the bottom.
C)The kelp lives in warm water.
D)The kelp fronds develop their leaves.
E)The kelp holdfast is large enough to be called a true root system.

Question 27

Kelp communities are severely disturbed by all of the following except:

A)Grazing sea urchins.
B)Grazing fishes.
C)Pollution.
D)Warm currents.
E)El Ni-o.

Question 28

Sea weed species with increased photosynthetic pigments for life in deeper waters are found in:

A)Red algae.
B)Brown algae.
C)Green algae.
D)All answers are correct.
E)Red algae and Brown algae only.

Question 29

The life cycle of the giant kelp involves:

A)One growth form.
B)Two growth forms.
C)Two growth forms,both very large.
D)Two or three growth forms,depending on temperature.
E)One growth form,which can be large or small depending on temperature.

Question 30

Which of the following strategies is not used by seaweeds to combat grazing?

A)Chemical defenses
B)Leathery consistency
C)Calcium carbonate
D)Bad taste
E)Slow growth