Organization & Niche
This level of organization includes all living things in a forest plus soil, water, and sunlight.
What is an Ecosytem?
Unlike matter, which cycles, this "flows" through an ecosystem and must be constantly supplied.
What is energy?
This "J-shaped" growth curve occurs when a population has unlimited resources.
What is exponetial growth?
This term describes the role or position an organism occupies within its ecosystem.
What is an ecological niche?
This process occurs when toxins become more concentrated at higher trophic levels.
What is biomagnification?
A single silver maple tree represents this most basic ecological level of organization.
What is an Indiviual/Organism?
According to the laws of thermodynamics, energy input must exceed loss to offset this state of disorder.
What is entropy?
To calculate the change in a population size over time, you must subtract deaths from births and also factor in these two types of "movement" into and out of the area.
What is immigration and emigration?
To avoid direct competition, species may occupy slightly different niches in this process.
What is Niche partitioning?
High levels of nitrates and phosphates in runoff frequently cause this in aquatic systems.
What is Eutrophication?
These organisms capture energy from small inorganic molecules to produce organic compounds.
What are chemoautotrophs?
This plant hormone facilitates phototropism by causing cells to grow longer on the shaded side of a stem.
What is auxin?
This term represents the maximum number of individuals an environment can support.
What is carrying capacity?
This specific type of species has an unusually large impact on its ecosystem relative to its abundance.
What is a keystone species?
High levels of this allow a population to respond better to environmental changes or diseases.
What is genetic diversity?
This specific growth response occurs when a plant bends toward a light source to maximize energy capture.
What is phototropism?
These organisms are essential to the nitrogen cycle because they convert atmospheric nitrogen for plants.
What are bacteria? Nitrogen-fixing bacteria specifically
Unlike natural disasters, competition for food is this type of "regulating factor."
What is a density-dependent limiting factor ?
The reintroduction of wolves to Yellowstone is an example of this multi-level ecosystem effect.
What is a trophic cascade?
Invasive species often grow exponentially because they lack these in their new environment.
What is natural predators? Or Outcompetiting Species
If a squirrel population has 100 births and 60 deaths in a year, what is the value of dn/dt? The answer must be in correct units also. Is the population increasing or decreasing?
What is 40 squirrels/year? Increasing.
If 85 cane toads are introduced to a habitat with an rmax of 0.25, how many are there after one year?
What is 106 toads?
A population of 450 trout in a lake with carrying capacity of 600 and a rmax of 0.5 will reach what size after one year? Answer must be in correct units.
What is 506 trout/year?
This mathematical tool is used by ecologists to measure biodiversity by taking into account both species richness and evenness.
What is Simpson's Diversity Index?
This phenomenon occurs when a population's size is drastically reduced by human activity, leading to a loss of genetic diversity that persists even if the population numbers recover.
What is the bottleneck effect? genetic bottleneck