Question
1 of 25
The lower limit of the intertidal zone is the
average high tide.
average middle tide.
lowest tide.
lowest edge of the rocky substrate.
None of the above choices are correct: it varies according to type of substrate.
Question
2 of 25
The particular characteristic most widely used in classifying intertidal communities is which of the following?
Type of tides
Relative exposure to air
Type of substrate
Type of seaweeds
Relative immersion by water
Question
3 of 25
Which of the following strategies is not used to avoid desiccation in the intertidal?
Closing shells
Crowding in areas that are always moist
Burrowing into substrate
Mucus
Moving out of tide pools
Question
4 of 25
Most sessile animals living on rocky shores are which of the following?
Deposit feeders
Carnivores
Detritus feeders
Filter feeders
Grazers
Question
5 of 25
If a rocky shore highly exposed to wave action is compared to a similar rocky shore that is a lot less exposed to wave action, one should expect that barnacles living on the more exposed shore show a
wider vertical distribution.
narrower tolerance to salinity.
narrower tolerance to temperature.
narrower vertical distribution.
higher resistance to predators.
Question
6 of 25
Byssal threads are used by mussels to cope with.
desiccation.
wave shock.
restricted feeding.
salinity changes.
temperature changes.
Question
7 of 25
Vertical zonation on rocky shores is mostly the result of differences in tolerance to
wave action.
exposure.
predation.
light.
salinity.
Question
8 of 25
This organism is typical of the upper intertidal on rocky shores.
Mussels
Barnacles
Sponges
Sea anemones
Periwinkles
Question
9 of 25
The middle intertidal is characterized by which of the following?
Constant wetting by splash and spray
Long exposure to air
Steady immersion
Exposure and immersion on a regular basis
Splashing during high tide and complete exposure at low tide
Question
10 of 25
Intertidal organisms from exposed areas sometimes have thicker shells than their counterparts from less exposed areas. This is thought to be an adaptation to
desiccation.
restricted feeding.
wave shock.
salinity changes.
temperature changes.
Question
11 of 25
Predation by sea stars on rocky shores ultimately results in
fewer species.
less wave action.
a decrease in the number of seaweeds.
an increase in the number of mussels.
more species.
Question
12 of 25
Ecological succession ultimately results in
a climax community.
an upper-limit stage.
competitive exclusion.
keystone predation.
vertical zonation.
Question
13 of 25
Which of the following is generally considered to be the greatest limiting resource in the rocky intertidal?
Salinity
Space
Prey
Availability of mates
Light availability
Question
14 of 25
Which of these organisms is typically a very rare component of soft-bottom intertidal communities?
Burrowing organisms
Detritus feeders
Seaweeds
Infauna
Deposit feeders
Question
15 of 25
Most animals living on sandy beaches are included among which of the following?
Infauna
Deposit feeders
Macrofauna
Producers
Grazers
Question
16 of 25
Fine sediments are characteristic of
shores exposed to wave action.
rocky shores.
areas with wide temperature fluctuations.
calm, less exposed shores.
areas that experience considerable water flow.
Question
17 of 25
The interstitial water in muddy bottoms
has plenty of oxygen since temperature is much higher than in the water column.
accumulates oxygen as a result of photosynthesis by inhabitants of the sediment.
recirculates oxygen very frequently so it is high.
is deficient in oxygen.
is deficient in oxygen but only during the day.
Question
18 of 25
The main source of food in muddy-bottom intertidal communities is
seaweeds
detritus
plankton
large prey
epifauna
Question
19 of 25
On Atlantic shores, the dog whelk (Nucella lapillus) has two color forms: white-shelled and brown-shelled. Survival of one form over the other form in a region appears to be related to
temperature.
salinity.
substrate type.
prey availability.
predators.
Question
20 of 25
What organism would be most likely to be found in the upper intertidal zone of a rocky shoreline?
Mussels
Seaweed
Encrusting algae
Barnacles
Irish moss
Question
21 of 25
In soft-bottomed intertidal communities, locations with strong waves and currents are most likely to have which type of bottom?
Gravel
Sand
Silt
Clay
Mud
Question
22 of 25
Meiofauna live
on rocky shores.
on sandy bottoms.
between grains of sediment.
in burrows.
in the water column.
Question
23 of 25
A species that significantly influences the structure and diversity of its community is a ______________.
predator species
keystone species
prey animal
primary producer
apex predator
Question
24 of 25
The best reason for putting a cage over certain organisms in an intertidal study area is so that __________________.
other organisms can be kept out of the study area
biologists can control when certain animals mate
their respiration rates can be measured
they can be removed from the area
body measurements can be taken
Question
25 of 25
Two sediments that are very rich in detritus are ______________.
sand and gravel
sand and clay
silt and gravel
clay and sand
silt and clay