Deck 16: Marine Communities

Question 1

What provides the raw material for large and complex food webs within an estuary?

A) The ocean bringing in nutrients
B) Salt-tolerant plants producing carbohydrates
C) Salt-tolerant plants being decomposed
D) The river depositing nutrient-rich sediments

Answer 1

C
Salt-tolerant plants in the estuary are able to grow very quickly. When they die, their decomposition and the rapid turnover of nutrients become important in the ecosystem. This is a common characteristic of estuaries. Information can be found in the section Marine Scientists Examples of Marine Communities.

Question 2

What do many deep water organisms use for feeding and the attraction of mates?

A) Keen eyesight
B) Bioluminescence
C) Sense of smell
D) Electrical impulses

Answer 2

B
Many deep water organisms use patterns of bioluminescence for a variety of purposes. They can attract prey while hiding their own shadow in the darkness. Also, there are organisms that flash particular patterns in an effort to attract a mate. Information can be found in the section Examples of Marine Communities.

Question 3

What can occur when organisms are exposed to air and sunlight?

A) Wave shock
B) Motility
C) Desiccation
D) Succession

Answer 3

C
Desiccation is the drying out of an organism. Motile animals can move towards water, but sessile organisms must await the return of water. They trap water within their shells to keep their gills moist. Some have a protective mucous which prevents water loss. Information can be found in the section Examples of Marine Communities.

Question 4

Why was the feeding strategy of Riftia worms such a mystery to scientists when they were first discovered?

A) These worms have no mouth.
B) These worms have no digestive tract.
C) These worms have no anus.
D) All of these choices

Question 5

What process re-establishes climax communities after a major disruption in the environment?

A) Progression
B) Carrying capacity
C) Desiccation
D) Succession

Question 6

What is a community?

A) A group of organisms of the same species
B) A group of interacting organisms of different species
C) The number of different species in an area
D) The largest marine ecosystem

Question 7

What is the name for the pelagic community that lives in the upper limits of the permanent darkness in the deep ocean?

A) Climax community
B) Rift community
C) Deep scattering layer
D) Benthic community

Question 8

What describes a fish species with a narrow tolerance of temperature changes?

A) Stenohaline
B) Eurythermal
C) Stenothermal
D) Euryhaline

Question 9

Why do tropical coral reefs prefer high wave energy locations?

A) They are hard enough to sustain themselves during the wave action.
B) They receive less sunlight in these areas.
C) They become the first to obtain dissolved gases and food particles.
D) They need high levels of sunlight.

Question 10

What is environmental resistance?

A) The decline in population growth
B) The effect of limiting factors on the environment
C) The maximum population growth in an environment
D) The movement of one population against another

Question 11

What is a niche?

A) An organism's physical location in a community
B) The amount of different species in a community
C) An organism's occupation in a community
D) The number of populations in a community

Question 12

What is the basis for life in the hydrothermal vent community?

A) The heated waters surrounding the vents
B) Chemosynthetic organisms
C) Whale falls
D) The biological productivity of the water above

Question 13

What is arguably the best-adapted organism for the deep uniform environment of the ocean?

A) Brittle stars
B) Anglerfish
C) Tripod dish
D) Gulper eels

Question 14

What do most deep water consumers depend on for survival?

A) The productivity of the water column above
B) Chemosynthetic productivity
C) The deep scattering layer of nutrients
D) Rift communities

Question 15

What community has the highest biomass per unit of surface area?

A) Rocky intertidal
B) Estuary
C) Sandy beach
D) Deep ocean

Question 16

What is water called when it is a mixture of both freshwater and seawater?

A) Estuarine water
B) Brackish water
C) Productive water
D) Semidiurnal water

Question 17

Which distribution is the rarest found in communities?

A) Random distribution
B) Uniform distribution
C) Clumped distribution
D) Normal distribution

Question 18

Where is there no deep scattering layer present?

A) Temperate oceans
B) Tropical oceans
C) Arctic oceans
D) All oceans have a deep scattering layer

Question 19

What determines the number and composition of the populations in a community?

A) Food
B) Light
C) Space
D) All of these choices

Question 20

What is the study of the balance between environmental factors and organisms in a community?

A) Ecology
B) Biodiversity
C) Niche
D) Ecosystem

Question 21

Which is not a characteristic of deep water animals?

A) Deep water organisms tend to move slowly.
B) Deep water organisms require little food to survive.
C) Deep water organisms tend to have a long life span.
D) Deep water organisms have a high metabolic rate.

Question 22

What phylum is the most successful and widely distributed in terms of parasites?

A) Nematoda
B) Annelida
C) Polychaeta
D) Mollusca

Question 23

What is the largest marine community?

A) Intertidal community
B) Photic zone community
C) Between the photic zone and the deep bottom
D) Deep bottom communities

Question 24

Vent communities are as strange as a lost valley of prehistoric dinosaurs.

Question 25

Deep scattering layers are best developed in regions with high surface activity.

Question 26

How much biomass in tropical coral reefs is attributed to the coral alone?

A) 15%
B) 30%
C) 50%
D) 75%

Question 27

If an environment is changed by disruption, a different climax community always establishes.

Question 28

Communities are dependent on the availability of substrate.

Question 29

What is a hardship for small organisms that are associated with living on a sandy beach?

A) Sand has sharp, jagged edges.
B) Capillary forces can pin organisms down within the sand.
C) Organisms have a hard time finding a firm footing when burrowing.
D) All of these choices

Question 30

What physical factors can the accumulation of coral and sediment change in the environment?

A) Ocean temperature and current patterns
B) Availability of food
C) Salinity
D) Density

Question 31

Many large intertidal plants must be slippery in addition to being strong and elastic to avoid being shredded by the intense wave energy of the intertidal.

Question 32

The carrying capacity is the number of individuals an environment can support.

Question 33

If an animal is tightly attached to the rocks during intense wave activity, it is said to be:

A) sessile.
B) motile.
C) desiccated.
D) benthic

Question 34

The usual rigors of the intertidal zone are less severe in the sandy intertidal than the rocky intertidal.

Question 35

What is the significance of the coral reefs of the Southern Line Islands?

A) they represent the southernmost tropical reefs
B) they are like coral reefs before the impact of humans
C) they are highly impacted by humans
D) they have few fish and no top predators

Question 36

Most tropical reefs form in areas with low wave energy so they are not crushed by the force.

Question 37

What is thought to aid the proliferation and spread of hydrothermal vents?

A) Seep communities
B) Climax communities
C) Whale falls
D) Succession

Question 38

The most successful organisms in a community have the most surviving offspring.

Question 39

What is a climax community?

A) The first community after a large disruption
B) A new, growing community
C) A stable, long-established community
D) The decline of a community after it peaks

Question 40

The conditions of the deep ocean-the eternal darkness, the cold, hypersaline water, and the high pressure-limits the extent of deep-ocean floor communities.

Question 41

In a stable community, multiple populations can occupy the same role to ensure biodiversity.

Question 42

The variety of appearances and protective demonstrations associated with organisms on the coral reef is a testament to the intense struggles in the ecosystem.

Question 43

What are some of the adaptations exhibited by organisms living in estuaries? How do pelagic species use estuaries to their advantage?

Question 44

What challenges are faced by coral reefs today? What is the advantage of living in the tropical ocean which contains few nutrients? Hint: include reference to the National Geographic segment about the Southern Line Islands

Question 45

Biodiversity is the role of species in a given area.

Question 46

What impact does environmental resistance have on a population? What kind of population distribution patterns occur in communities?

Question 47

What are the types of symbiotic relationships that organisms exhibit? Give examples of each.

Question 48

Marine communities evolve more rapidly than terrestrial communities.

Question 49

What happens to climax communities after a disruption? How do these communities re-establish themselves after a disruption like a tropical storm? What is this process called?

Question 50

More than half of the animal species, marine and terrestrial, are not considered to be free-living.