growth in a new area; ex. on a newly formed volcanic island
branch of biology dealing with interactions among organisms and between organisms and the environment
all species in a given area; ex. all organisms in Flower Mound
process in which bacteria convert nitrogen into a form plants can use
consists of all ecosystems of one type; ex. tropical rainforest
term that means nonliving
organism that eats consumers
limiting factor whose effect is the same regardless of population size
examples of density independent limiting factors
earthquake, drought, severe frost, fire
symbiotic relationship in which one species benefits, but the other is harmed
the original source of energy in most ecosystems
rapid increase in population numbers due to unlimited resources
symbiotic relationship in which both species benefit
term that means living
combined portions of Earth in which all living things exist
organism that eats producers
symbiotic relationship in which one species benefits, and the other is unaffected
limiting factor whose effect increases with population size
examples of density dependent limiting factors
disease, parasitism, emigration, competition
"job" of an organism in the environment
organism that eats both producers and consumers
each step in the transfer of energy and matter within a food web
growth in an area has been disrupted and begins again; ex. on an abandoned field
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
an organism that can make its own food through photosynthesis or chemosynthesis
the day to day conditions of temperature and precipitation in an area
movement of organisms into a population/area
one species in a given area; ex. all squirrels in Flower Mound
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
What percentage of energy is transferred from one trophic level to the next?
an organism that cannot make it own food and must eat other organisms for food
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
relationship in which one species captures and feeds on the other
movement of organisms out of a population/area
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
pyramid that shows the amount of energy at each level
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.