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70 Cards in this Set

  • Front
  • Back
the scientific study of the interaction of organisms with their living and nonliving environments
the individuals of a same species within a given area at the same time
population structure
the distribution of the ages of individulas in a population and the way those individuals are distributed over the environment
population density
the # of individulas of a species per unit (or volume)
How is pop. density measured on land?
individulas per unit area
How is pop. density measured in water?
individulas per unit volume
the study of birth, death, and movement rates that give rise to population dynamics

# of individuals at time 1

# of individuals at time 0

# of individulas born

# of individuals died

# of individuals that immigrated

# of individuals that emigrated
mutalism (+/+)
both participants benefit from an interaction
commenalism (+/0)
one participant is benefited but one participant remains unaffected
amensalism (0/-)
one participant is harmed but the other is unaffected
predator-prey and parasite-host(+/-)
one organism may benefit while harming another organism
competition (-/-)
two organisms use the smae resources and those resources are insufficent for their combined needs
what factors influence pop. density?
1. abundant resources
2. size of individuals
3. newly introduced invasive species
4. complex social organizations

the change in the # of individuals/pop.size

the change in time

the average per capita rate (both births and immigrations)

the average per capita death rate (includes both deaths and emigrations)

population size
carrying capacity of the environment
nonliving covering that provides an animal with both protection and support
layers of protein and a strong, flexible, waterproof polysaccharide
phylum Hexapoda
the insects
A substantial change that occurs between one developmental stage and another
The immature stages of insects between molts
incomplete metamorphosis
the changes between its instars are gradual
complete metamorphosis
the larval and adult forms appear to be completely different animals
intermediate disturbance hypothesis
Although the consequences of various kinds of disturbances are highly variable, their results conform to a general pattern
net primary production
The energy available to organisms that eat plants
ecological succession
A change in community composition following a disturbance
gross primary productivity
The rate at which energy is incorporated into the bodies of photosynthetic organisms
trophic levels
Divisions of organisms in a community based on the way in which they obtain their energy
species richness
The number of species living in a community
ecological community
The species that live and interact in an area
Gross primary productivity
the rate at which energy is incorporated into the bodies of photosynthetic organisms
primary production
the energy that is incorporated into the bodies of photosynthetic organisms
net primary
The energy available
to organisms that eat plants, gross primary production
minus the energy expended by the plants on
their respiration
competitive exclusion
interspecific competition becomes more intense
when productivity is higher
Photosynthetic plants that get their energy directly
from sunlight. Collectively, they constitute a trophic
level called photosynthesizers, or primary producers. They produce
the energy-rich organic molecules that nearly all other
organisms consume.
all nonphotosynthetic organisms that consume, either directly or indirectly,
the energy-rich organic molecules produced by primary producers.
herbivores or primary consumers
Organisms that eat plants and constitute a trophic level
secondary consumers
Organisms that eat herbivores
detritivores or decomposers
Organisms that eat the dead bodies of organisms or their
waste products
that obtain their food from both primary producers and
another trophic level are
food chain
Asequence of interactions in which a plant is eaten by an
herbivore, which is in turn eaten by a secondary consumer,
and so on
food web
an interconnection of food chains
energy pyramids
To show how energy decreases as
it flows from lower to higher trophic levels
the amount of living
matter at each trophic level
biomass pyramids
To show the biomass
of organisms existing at different trophic levels, illustrates the
amount of biomass that is available at a given time for organisms
at the next trophic level
keystone species
Species whose influences on ecosystems are greater than
would be expected on the basis of their abundance, may influence both the
species richness of communities and the flow of energy and
materials through ecosystems
an event that changes the survival rate of one
or more species in an ecological community
intermediate disturbance hypothesis
explains the low species richness in areas with high disturbance
levels by suggesting that only species with great dispersal
abilities and rapid reproductive rates can persist in
such areas. Conversely, the hypothesis explains the decline
in species richness where disturbance levels are low by suggesting
that competitively dominant species displace other
what The melting and
retreating of a glacier leaves, a series of gravel deposits
formed where the glacial front was stationary for a number
of years
A primary succession
begins on sites that lack living organisms
A secondary
begins on sites where some organisms have
survived the most recent disturbance
of individuals out of the area
of individuals into the area
exponential growth
If births and deaths
occur continuously and at constant rates, a graph of the
population size over time forms a continuous, J-shaped curve
logistic growth
Because of environmental limits, the growth of a population
typically slows down as its density approaches the environmental
carrying capacity. Agraph of the population size
over time results in an S-shaped curve
per capita birth and death rates change
in response to population density
Factors that change per capita birth and death
rates in a population independently of its density
The process of shedding part or all of an outer covering
Fragmented habitat
Habitat patches that have become smaller and more isolated due to the destruction of larger habitats by human activities
The species that form an ecological community, together with the physical environment
rescue effect
The population as a whole consists of numerous subpopulations confined to suitable habitats and maintained by immigration of individuals between populations