Chapter 15

These organisms are inhabitants of a/an:

hydrocardon seep

Coral reefs contain 25% of all known marine species.

true

Pisaster (sea star)

low tide zone

sea anemone

low tide zone

sand dollar

sandy beaches

A. buckshot barnacle B. chiton C. hermit crab D. limpet E. periwinkle

C. hermit crab

Of the following adaptations, which apply to life in intertidal environments?

ALL but burrowing

Of the following environments, which support(s) chemosynthesis?

ALL but in mid-water

Along a rocky shore, the spray zone is indicated by the number:

1

Recent studies indicate that the deep biosphere, an environment that exists within the seafloor itself, may account for up to _________ of Earth's total bacterial biomass.

2/3

The area on a rocky shore inhabited by organisms adapted to withstand wave energy for the majority of the tidal cycle is indicated by the number:

7

Of the following statements about coral reefs, which is/are true?

The biomass of coral reefs is composed mostly of algae. Reef corals need warm, tropical waters. Most coral reefs exist in nutrient-poor waters, so corals have symbiotic algae in their tissues that provide them with food.

Of the following statements about kelp and kelp forests, which is/are true?

The giant brown bladder kelp Macrocystis can grow up to 0.6 meter (2 feet) a day, making it the fastest-growing alga in the world. Kelp in kelp forests is held to the bottom by a strong anchor called a holdfast.

Of the following statements about organisms in rocky intertidal zones, which is/are true?

The low tide zone holds the greatest number of soft-bodied organisms and marine algae. Mussel beds are a common feature of the middle tide zone. The spray zone is where organisms with shells are mostly found.

As a citizen scientist you have been selected to participate in a once-in-a-lifetime journey to ride along in a deep-sea submersible to explore life in the bathypelagic zone of the ocean. As you descend you anticipate nothing but abyssal plains, but what you see instead is an oasis of life dominated by the tubeworm Riftia! Later you learn that the results of the biological survey reveal that even though this community has 1,000 times more biomass than surrounding deep-sea habitats, the overall diversity is very low. Considering these results, the deep-sea community you visited was

a black smoker releasing water at a temperature near 400 ∘C

In which sediment-covered shoreline would you find the greatest concentration of subsurface-dissolved oxygen?

a steeply sloping beach face composed of cobble stone

Sewage discharge and fertilizer runoff is detrimental to coral growth because it increases the:

amount of inorganic nutrients in the water that stimulates excessive algal growth.

Two dominant organisms of the rocky shore found high on the rocks of the intertidal zone are:

buckshot barnacles and limpets.

The most successful adaptation for living on a sediment-covered shore is:

burrowing into the sediment

Intertidal zonation across a sediment-covered shore is best seen when the shore is gently sloping.

false

The supratidal zone of the rocky shore is the area between the highest high tide and the lowest low tide.

false

Some organisms living in the high water portion of the intertidal zone cannot survive in the supralittoral zone because they:

have planktonic larval forms.

Littorina (periwinkle snail)

high tide zone, supratidal zone

The subtidal rocky bottom zone along temperate shorelines is dominated by:

kelp.

The loss of color (coral bleaching) in coral reef organisms can be a result of:

loss of zooxanthellae.

The common annelid found in a sandy beach environment is the:

lugworm

Mytilus (mussels)

middle tide zone

hermit crab

middle tide zone, tide pool

Organic matter decomposes most slowly in

mud flats

The symbiotic relationship between the coral animals and the zooxanthellae is an example of

mutualism

The relationship between the protistan zooxanthellae and the polyps of reef-building corals is best described as a/an:

mutualistic symbiosis.

The distribution of benthic biomass is related to:

primary productivity.

The organism posing the greatest threat to the kelp forest is the

sea urchin

Benthic animals inhabiting the rocky intertidal environment consist mostly of

sessile animals, nektobenthos, and very few infauna

The most important limiting factor in rocky intertidal communities is:

space

kelp

subtidal rocky bottoms

All of the following are true of corals except :

the distribution of reef-building corals is greater in the tropics.

Coral reefs contain more algal biomass than animal biomass.

true

Hermit crabs are commonly found inhabitants of tide pools.

true

Kelps with air bladders are common along the western and northwestern Pacific coasts of the United States.

true

One characteristic of hydrothermal vent communities is the unusually large size of organisms such as tubeworms and clams.

true

Some of the more common fauna of sediment-covered shores include bivalve mollusks, annelid worms, and crustaceans.

true

The Crown of Thorns sea star may be increasingly more common because its predators are fish species belonging to populations that have dramatically decreased due to overfishing.

true

The temperature of the ocean water has a significant effect on species diversity of benthic communities.

true

All of the following are associated with hypersaline seeps except:

very high temperature.