Trophic Cascades
What is a trophic cascade?
The indirect effects that impact ecosystems beyond just their trophic level.
The accumulation of harmful chemicals in organisms through trophic levels.
Predation
What is a habitat?
r-types - frogs, mice, oysters, rabbits
K-types - humans, elephants, gorillas, kangaroos
An organism that has a larger influence on its ecosystem than other organisms.
What is one of the toxic substances we have referenced in regards to bioaccumulation?
DDT, Mercury (Hg), Lead (Pb)
Intraspecific competition
Interspecific competition
What are limiting factors and how are they related to carrying capacity?
Limiting factors control the numbers of a population and determine how large it can grow, which is known as the carrying capacity.
A rainforest with top level predators and a rainforest without top level predators. Explain the difference in producers in these ecosystems.
Rainforests without predators have less vegetation because there are no predators to control the herbivore population.
Through producers, who are then eaten by consumers
Explain the difference between mutualism and commensalism.
In mutualism, both species benefit.
In commensalism, one species clearly benefits, while the other is mostly unaffected by the other.
Parasitism.
Draw a model of an exponential growth curve and a logistic growth curve.
Exponential should start slow and grow faster each interval.
Logistic should start fast until it gets closer to a limit known as the carrying capacity before it levels off.
Draw a model of the trophic cascade involving otters, urchins, and kelp in the Pacific Northwest. Include all arrows and signs.
Otters - Negative direct effect on urchins, positive indirect effect on kelp.
Urchins - Negative direct effect on kelp
Humans consume a large amount of tuna. Explain how mercury from mining industries are a danger to our tuna supply.
Mercury makes it to the water and is taken up by phytoplankton, which are then consumed by larger organisms, before being eaten by tuna.
What is succession?
The progression of an ecosystem after a disturbance as it goes from less to more biodiverse.
What is the difference between a habitat and a niche?
Explain the difference between density-dependent and density-independent limiting factors. Provide an example of each.
Density-dependent factors are determined by how many members are in a population, such as food, space, water, or disease.
Density-independent factors disregard population density and will affect a population regardless, such as natural disasters.
Draw a model of the trophic cascade involving otters, urchins, and kelp in the Pacific Northwest that also includes orca. Include all arrows and signs.
Orcas - Negative direct effect on otters, positive effect on urchins
Otters - Negative direct effect on urchins, positive indirect effect on kelp.
Urchins - Negative direct effect on kelp
Draw a model that shows the process of bioaccumulation.
Contaminants should accumulate through higher trophic levels.
Draw a model of primary succession. Include a timeline.
Should show the transition from rock into soil before turning into plant life. Should take a long time.
Draw a model of secondary succession. Include a timeline.
Should show the soil remaining intact after a fire or storm. Should be significantly faster.
What is the population growth rate formula and what do the variables stand for?
r = ((B+I)-(D+E))/N
r=population growth rate, B=births, I=immigrants, D=deaths, E=emigrants, N=total population