Review 1
What is an independent variable?
The variable changed by the experimenter between each treatment group
What is sustainability?
The ability to meet current needs without compromising the ability of future generations to meet their own needs
A student sets up an experiment to test how different brands of fertilizer affect duckweed growth. What is their independent variable?
Brand of fertilizer
What is mutualism?
both organisms benefit
A student sets up an experiment to test how different brands of fertilizer affect duckweed growth. What is their dependent variable?
Duckweed growth
What is a dependent variable?
The variable that is measured by the experimenter
Define organism and population
O: any living thing
P: all the organisms of one species in a given area at a given time
Where did all the energy contained in an ecosystem originally come from?
The sun
What is parasitism?
One benefits, one is harmed
What is the difference between primary and secondary succession?
Primary is the change in species composition in an area beginning from bare rock, while secondary begins after a disturbance such as a fire
What is a controlled variable?
A variable that stays the same between each treatment group
Define community and ecosystem
C: all the populations of different species in an area
E: the community + the physical environment
What is a trophic cascade?
When one trophic level gets disrupted, it has a domino effect and other levels are also impacted
What is commensalism?
One benefits, one unaffected
What are the pioneer species for primary and secondary succession?
P: Lichen
S: Grasses
What is a control group?
The group that does not receive the independent variable
Define biome and biosphere
Biome: large area of land characterized by shared climate, soil, vegetation, etc
Biosphere: the area of Earth where life exists
What is the difference between an autotroph and a heterotroph?
A: produces its own food
H: must consume other organisms to get food
What is amensalism?
One harmed, one unaffected
How can humans impact the nitrogen and phosphorus cycles?
Using fertilizers
Name four things you would check to see if a source is reliable
Author's credibility, date published, website/publisher credibility, citing their sources, not trying to sell you anything, etc
What's the difference between biotic and abiotic factors?
Living vs. nonliving things in an ecosystem
Explain the tragedy of the commons
The idea that if there is an unregulated shared resource, humans will overuse it until it is gone
Describe the process of eutrophication, including fertilizer, algae, bacteria, and oxygen.
Fertilizer runoff pollutes the water, causing an algal bloom. This algae can grow so thick it covers the surface of the water and blocks the sun. Dead plants and algae build up, leading to an increase in bacteria, who feed off of dead things. The bacteria use up all the oxygen in the water, killing all life.
How can humans impact the carbon cycle?
Burning fossil fuels, breathing out CO2, decomposition, eating organisms that contain carbon