The lower limit of the intertidal zone is

a) average high tide

b) average middle tide

c) lowest tide

d) lowest edge of the rocky substrate

e) none of the above: it varies depending on type of substrate

The particular characteristic most widely used in classifying intertidal communities: A)type of tides B)relative exposure to air C) type of substrate D)type of seaweeds E)relative immersion by water

Regarding the origin of rocky coasts, it is known that this type of shore is present along: A) geologically young coasts B)coasts with high accumulation of sediments C)coasts along the mouth of large rivers D)geologically old coasts being covered by sediments E)coasts being affected by ice sheets

The sessile epifauna consists of: A)attached seaweeds B)pelagic organisms C)burrowing animals D)animals that crawl over bottom E) attached animals

Many rocky-shore animals cope with desiccation by: A)moving up the intertidal B) crowding in areas that are always moist C)opening their shells D)expanding or elongating their soft bodies E)moving out of tide pools.

Most sessile animals living on rocky shores are: A)deposit feeders B)carnivores C)detritus feeders D) filter feeders E)grazers

One of these organisms is expected to be relatively rare on a rocky shore: A)filter feeder B)carnivore C)primary producer D)grazer E) deposit feeder

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, we should expect that barnacles living on the more exposed shore show a: A) wider vertical distribution B)narrower tolerance to salinity C)narrower tolerance to temperature D)narrower vertical distribution E)higher resistance to predators

The reason why rocky shores have few deposit feeders: A)abundant detritus B) high wave action C)numerous carnivores D)no filter feeders E)high salinity

Refraction causes waves to: A)slow down B)approach the shore at an angle C)become more parallel to the shore D)break E) speed up

One of these is more important than the others as a limiting resource in intertidal communities:A) spaceB)food C)nutrients D)light E)salinity

The upper limit of rocky intertidal communities is typically determined by: A)biological factors only B) physical factors only C)biological and physical factors D)neither physical or biological factors

The middle intertidal is characterized by: A)constant wetting by splash and spray B)long exposure to air C)steady immersion D) exposure and immersion on a regular basis E)splashing during high tide and complete exposure at low tide

Predation by sea stars on rocky shores ultimately results in: A)fewer species B)less wave action C)decrease in the number of seaweeds D)increase in the number of mussels E) more species

In addition to space, another factor that is typically limiting in the lower intertidal along rocky shores: A)salinity B) grazing C)temperature D)type of substrate E)nutrients

Fine sediments are characteristic of: A)shores exposed to wave action B)rocky shores C)areas with wide temperature fluctuations D) calm, less exposed shores E)areas that experience considerable water flow

In terms of oxygen, the interstitial water in muddy bottoms: A)has plenty of it since temperature is much higher than in the water column B)accumulates it as a result of photosynthesis by inhabitants of the sediment C)recirculates very frequently so it is high D) is deficient in it E)is deficient in it but only during the day .

The main source of food in muddy-bottom intertidal communities: A)seaweeds B) detritus C)plankton D)large prey E)epifauna

Coastal plain estuaries were formed when: A)sand bars formed along the coast as the result of an accumulation of sediment B) the ocean invaded lowlands and rivermouths C)retreating glaciers cut a valley along the coast D)sea level fell during glaciation E)land subsided along the coast.

Good examples of bar-built estuaries are found here: A)coast of Norway B)Pacific coast of the United States C) Atlantic Coast of the US D)Chesapeake Bay E)St. Lawrence River

Fjords are formed as a result of the: A)subsidence of land B)lowering of sea level C)formation of sand bars and barrier islands D)the coast is cut by a river E) raising sea level

In an estuary, salinity of the water increases as; A)one moves inland B)depth decreases C)evaporation decreases D)freshwater flow from a river increases E) depth increases

The salt wedge of an estuary: A) moves inland as a tide moves in B)is found in shallower water as one moves inland C)decreases the average salinity of the estuary D)decreases the distribution of marine organisms along the bottom of the estuary E)spreads further into the estuary as the flow of freshwater increases

Tidal bores in estuaries result from the effect of: A)freshwater moving from rivers B)the Coriolis effect C) high tides moving in D)salt wedge moving toward the surface E)differences in water temperature as one moves inland

The most common type of substrate in estuaries: A) mud B)rock C)coarse sand D)fine sand E)none of the above: it depends on the salinity

The amount of hydrogen sulfide in the sediment increases as the following factors increase except one: A)oxygen B) space between sediment particles C)size of sediment particles D)amount of organic matter E)amount of detritus

Euryhaline species: A)are less common in estuaries than stenohaline species B)need less oxygen to survive C)tolerate only a narrow range of salinities D) can survive changes in salinity E)only tolerate small temperature changes.

Osmoconformers survive changes in salinity by: A)maintaining the salinity of their body fluids constantly B)moving up and down the water column in order to spend most of the day in the salt wedge C)pumping water in as salinity decreases D) allowing the salinity of their body fluids to vary with that of the surrounding water E)increasing the amounts of salts in their body fluids no matter what the salinity of the surrounding water is

Salmon, which migrate between the sea and rivers, are an example of: A)osmoconformers B)stenohaline species C)catadromous species D)perfect osmoconformers E) osmoregulators

The most important difference between muddy intertidal shores and the mud flats of estuaries: A)type of substrate B) variation in salinity C)amount of light D)exposure to wave action E)size of sediment particles

An example of a primary producer on mud flats: A) benthic diatoms B)phytoplankton C)kelp

D)surf grass E)mud snails

An example of a deposit feeder on mud flats: A) mud snail B)birds that feed on worms C)clams D)sulfur bacteria E)worms that feed on other worms

The most abundant type of mud-flat organisms: A)carnivores B)epifauna C)seaweeds D) infauna E)filter feeders

Succulents are plants that: A)excrete salts by way of salt glands B)lose water and salts C) accumulate water in their tissues D)take in salts to compensate for the loss of water E)do not have any roots to minimize water loss

The infauna of mud flats feeds mostly on: A)epifauna B)sulfur bacteria C)filter feeders D)plankton E) detritus

Blood rich in hemoglobin is an adaptation to: A)fluctuating salinities B)wide variations in temperature C)soft sediments D)feeding in detritus E) low oxygen concentrations

The zonation of plants in salt marshes is determined mostly by: A)temperature fluctuations B)geographical location C) height of the tide D)amount of oxygen in sediments E)detritus in the water

The food web in salt-marsh communities is characterized by high primary production. Most of this production is made available to other communities in the form of: A)plant tissue eaten by grazers B)plankton eaten by filter feeders C) detritus D)plants eaten by herbivores E)plants eaten by zooplankton

The geographical distribution of mangrove forests is mostly determined by: A)salinity B)type of sediment C) temperature D)wave action E)height of tide

Mangrove forests are considered a stage in the ecological succession between marine and terrestrial communities due to the fact that they: A) accumulate sediment in their roots B)produce large amounts of detritus C)serve as a nesting place for birds D)maintain a large concentration of nutrients E)live mostly above water

Outwelling in estuaries is most important since it: A)maintains high primary production B)provides living space to many species C)releases much oxygen D) provides food and nutrients to other communities E)allows plants to survive despite wide fluctuations in salinity