Before the invention of the Haber-Bosch process, farmers had to rely on these bacteria to break the the triple bond keeping atmospheric nitrogen in the air.
What are nitrogen-fixing bacteria?
The atoms of this element are essential for building proteins. Too bad the triple bond connecting the elemental form of this substance in our atmosphere is so tough to crack.
What is nitrogen?
These factors slow population growth as the population increases in a given area. Crab cannibalism, parasites, and intraspecific competition are a few examples.
Negative density dependent factors
The biodiversity of a habitat can be measured by counting the species - and by this metric, which represents the relative abundance of each species.
What is species evenness?
What is a carbon sink?
This process - largely caused by fertilizer-depositing runoff - can lead to dissolved oxygen levels outside the range of tolerance for many fish species.
What is eutrophication?
Largely due to heat, only about this much energy can be transferred up the food chain.
What is 10%?
Symbolized by K, this number represents the limit of a population that an ecosystem can sustain.
What is carrying capacity?
While generalists can thrive in a variety of niches, these species were forced to adapt to unique habitats.
What are specialists?
Countries in this stage of the demographic transition might face the problem of negative population growth.
What is the postindustrial stage? (Stage 4)
In the nitrogen cycle, these bacteria help return nitrogen gas back to the atmosphere.
What are denitrifying bacteria?
Not mutualism. Not parasitism. This relationship is win-neutral.
What is commensalism?
The rule of 70 - divide 70 by the growth rate, r - can be used to quickly predict this about a population.
What is doubling time?
Area and isolation are two characteristics that help ecologists predict biodiversity on these.
What are islands?
It was a rough first week. Only about 10% of the kids made it.
What is a type III survivorship curve?
NPP = GPP - the energy used in this process.
What is plant respiration?
This biome has relatively stable temperatures, precipitation, receives a high level of solar energy, and is characterized by the highest level of primary productivity.
What is tropical rain forest?
This stage of the demographic transition is best characterized by population growth that is supported by a substantially decreased mortality rate.
What is the transition stage?
When biodiversity decreases with distance from the mainland, the MIX is this...
What is distance from the mainland?
Calculate the time it would take a population to double if the annual growth rate was 2.0%?
35 years
This type of habitat is found where river meets ocean and includes waters with varying degrees of salinity, turbidity, and dissolved oxygen levels. 
What is an estuary?
Species like these such as lichen and moss typically initiate primary succession.
What are pioneer species?
These species have evolved to mature rapidly and produce many offspring, usually only once in a lifetime.
What is r-selected?
When species richness increases as the island area increases, the DRY is this...
What is species richness?
This part of a study or experiment is what researchers manipulate.
What is the independent variable?