LS 7B Week 9

mutualism

(+,+) Both organism benefit

competition

-/- competes for resources, can reduce surviorship, density dependent, - affects all indiv involved

The sequence of species that colonize a recently disturbed area through succession is unpredictable.

False

In the example of the giant kelp forests on the Pacific coast, a rise in the otter population would have what effect on the kelp populations?

Kelp populations would increase due to a decrease in sea urchins.

What is generally true about biomass and energy as we move from one trophic level to the next?

Not all energy is transferred to the next trophic level.

A gardener treats his plants with pesticides, killing any aphids. Once the aphids die, what likely happens to the mutualistic bacteria inhabiting their digestive tracts?

The bacteria would likely die without their mutualistic aphids, as this is an example of an obligate relationship.

Symbiotic relationships are subject to natural selection.

True

While food chains show linear energy transfer between organisms, food webs depict more realistically what occurs in an ecosystem.

True

Which factors contribute MOST to intraspecific competition?

a species' rate of reproduction and the carrying capacity of the environment

realized niche

acutal niche species occupies

island biogeography

arrival rate of new species decreases as species accumulate; extinction rate increases as individuals from different species compete for resources

When would a researcher be MOST likely to observe resource partitioning?

between two sympatric species that eat similar-sized seeds

facultative mutualism

both species can survive alone

When two species compete for resources, the fitness of:

both species will decline.

A species that is involved in a facultative mutualism with another:

can utilize a variety of different resources.

When both participants in a species interaction develop adaptations in direct response to one another, in the long term this could progress into:

coevolution

The human body has about 10 bacterial cells for every eukaryotic cell. Bacteria coat our skin, gut, and mouth. Also present are protists, Archaeans, and viruses. Collectively, these organisms are our microbiota. For most members of our microbiota, our body provides their environment (or space to live). They, in turn, have no effect on us. This is an example of:

commensalism.

The sum total of the populations that live in a given area is called a(n):

community

Which of the following is a type of interaction in which BOTH parties are harmed?

competition

interspecific competition

competition between members of different species

intraspecific competition

competition between members of the same species

In the late 1960s, Robert Paine conducted landmark studies on diversity in the rocky intertidal zone, comparing the species diversity in control plots with diversity in experimental plots from which he removed the top predator, sea stars. After 5 years, 15 species of intertidal invertebrates lived in the control plots, while the experimental plots were dominated by only two species, one mussel and one barnacle. The process MOST likely responsible for the loss of species diversity in the experimental plots was:

competitive exclusion

Benefits associated with symbiotic relationships might include all of the following EXCEPT:

competitive exclusion.

Which group in a food web is responsible for returning inorganic compounds back to the environment?

decomposers

You decide to plant a garden in your backyard. You dig up a strip of grass in a sunny spot. When you have finished digging up the grass, but you haven't planted anything, you have created a(an) _____ in the lawn.

ecological disturbance

biodiversity leads to?

ecological resilience as diverse gives functionally redundant so more resilient to change

A(n) _____ is a community of organisms and the physical environment it occupies.

ecosystem

Keystone species can have significant influences over several populations in a community through their:

effect on high amounts of biomass and energy transfer between populations.

The bacterial species <i>Staphylococus</i> <i>aureus</i> is found on the skin and in the nasal passages of about 20% of the human population. It can survive on polyester for 3 months and can also infect cows and chickens. Thus, its relationship with humans is:

facultative

Predator/prey relationships are always linear, with one species affecting only one other in the community.

false

effect of distance for an island?

far islands have lower colonization rates

A _____ depicts the flow of carbon through an ecosystem, whereas a _____ depicts the transfer of energy.

food web; trophic pyramid

Imagine that a scientist takes a group of Anolis lizards and introduces them into an enclosure at a research facility in continental South America. He notes that the lizards thrive in this new environment. The fact that Anolis lizards could survive in habitats outside of the Caribbean is a reflection of their _____ niche; their _____ niche is determined by predation and resource availability.

fundamental; realized

A species that has a disproportionately large effect on a community is called a _____ species.

keystone

island

metapopulations separated in space

Some species of ant "farm" aphids by protecting them from predators. In return, the ants feed on a sugar-rich liquid (called honeydew) secreted by the aphids. The ecological relationship between the ants and the aphids is:

mutualism

fundamental niche

niche a species could occupy

A mutualism in which the survival of one or both participants is dependent on the other is:

obligate

obligate mutualism

one species cannot survive without the other

Which of the following is a good predictor of biodiversity in terrestrial ecosystems?

plant species in a community

Measuring its costs and benefits in terms of energy spent and/or gained, which interaction(s) involve(s) one individual gaining and one individual losing?

predation

Organisms that take up inorganic nutrients and convert them to organic molecules such as carbohydrates and proteins are called:

primary producers

The broadest level in a trophic pyramid is primarily composed of:

primary producers.

The _____ of a species is usually the result of predation, competition, and other types of interaction between species.

realized niche

Which of the following is expected to reduce competition among individuals?

resource partitioning

Overlap of niches can be minimized through:

resource partitioning.

resource partitioning

result in niche specialization; temporal and spatial

Measuring its costs and benefits in terms of energy spent and/or gained, mutualism:

results in gain for both individuals.

ecological niche

role of the species in the ecosystem

Following a disturbance, the process by which species replace each other over time is/are called:

succession

Close interactions that have evolved over time between species are called:

symbioses

Which of the following graphs represents the change in fitness when there is competition between these species for the same resource?

that competition reduces fitness for both competing species because energetic expenditure occurs. There will be a reduction in fitness for both species.

Energy flow through ecosystems can be depicted using a(n):

trophic pyramid.

Niches are dynamic, and are affected by interactions among species.

true

The fact that diverse types of Anolis lizards inhabit (or hunt in) different levels of the tree canopy is the result of the effects of resource partitioning.

true

While biodiversity includes the number of species in a given area, it also includes:

unique phylogenetic lineages.