Unit 5A Review Flashcards
growth in a new area; ex. on a newly formed volcanic island
primary succession
branch of biology dealing with interactions among organisms and between organisms and the environment
ecology
all species in a given area; ex. all organisms in Flower Mound
community
process in which bacteria convert nitrogen into a form plants can use
nitrogen fixation
consists of all ecosystems of one type; ex. tropical rainforest
biome
term that means nonliving
abiotic
organism that eats consumers
carnivore
limiting factor whose effect is the same regardless of population size
density independent
examples of density independent limiting factors
earthquake, drought, severe frost, fire
symbiotic relationship in which one species benefits, but the other is harmed
parasitism

the original source of energy in most ecosystems
sunlight

rapid increase in population numbers due to unlimited resources
exponential growth

symbiotic relationship in which both species benefit
mutualism

term that means living
biotic
combined portions of Earth in which all living things exist
biosphere
organism that eats producers
herbivore

symbiotic relationship in which one species benefits, and the other is unaffected
commensalism

limiting factor whose effect increases with population size
density dependent
examples of density dependent limiting factors
disease, parasitism, emigration, competition
“job” of an organism in the environment
niche
organism that eats both producers and consumers
omnivore

each step in the transfer of energy and matter within a food web
trophic level

growth in an area has been disrupted and begins again; ex. on an abandoned field
secondary succession
What happens to the energy that is not passed to the next trophic level?
released as heat

How do prey population numbers affect predator population numbers?
They are dependent on one another. If prey numbers go up, predator numbers go up. If predator numbers go up, prey numbers go down.
leveling off of population numbers due to limited resources
logistic growth
an organism that can make its own food through photosynthesis or chemosynthesis
autotroph

the day to day conditions of temperature and precipitation in an area
weather
movement of organisms into a population/area
immigration
one species in a given area; ex. all squirrels in Flower Mound
population
an organism that obtains nutrients by breaking down dead organisms
decomposer; ex. fungi and bacteria

average year after year conditions of temperature and precipitation in an area
climate
What percentage of energy is transferred from one trophic level to the next?
10%
an organism that cannot make it own food and must eat other organisms for food
heterotroph
What do the arrows in a food web or food chain indicate?
the direction of energy flow; prey–>predator

Where is most energy and matter located in an ecological pyramid?
at the bottom
a pyramid that shows the amount of living tissue at each level
biomass pyramid
relationship in which one species captures and feeds on the other
predation
movement of organisms out of a population/area
emigration
pyramid that shows the number of organisms at each level
pyramid of numbers
What happens to a population that exceeds its carrying capacity?
population numbers drop due to lack of resources
relationship in which two species fight over the same resource
competition

pyramid that shows the amount of energy at each level
energy pyramid
Compare the movement of energy to the movement of nutrients in an ecosystem.
Energy moves in only one direction, but nutrients recycle.
Name 2 factors that would increase population numbers.
increasing birth rate and decreasing death rate
Name 2 factors that would decrease population numbers.
decreasing birth rate and increasing death rate
How does the amount of DDT change as it moves along a food chain?
increases at each level (biomagnification)

How does the amount of energy change as it moves along a food chain?
decreases at each level (only 10% is passed from level to level)
Identify the trophic levels of each organism in this food chain.

Leaf–producer, Caterpillar–primary consumer(herbivore,) Chameleon–secondary consumer, Snake–tertiary consumer, Mongoose–quaternary consumer
The grass has 100% energy. Following the 10% rule, what energy percentages will the remaining organisms have?

Grass–100%, Grasshopper–10%, Mouse–1%, Owl–0.1%
Each organism gets 10% of the energy from the previous organism.