Flow of Energy
This group of organisms forms the base of most ecosystems by converting solar energy into usable chemical energy.
What are autotrophs or producers?
A tick feeding on a host is an example of this type of symbiotic interaction.
What is parasitism?
This term describes a series of predictable changes in species composition following a disturbance.
What is ecological succession?
In a food web, this trophic level consumes producers.
What are primary consumers?
This term refers to the total number of different species in a community.
What is species richness?
These organisms feed on detritus and help recycle organic material back into the ecosystem, making them crucial in nutrient cycling.
What are decomposers or detritivores?
Lichens are a classic example of this symbiotic relationship between a fungus and an alga or cyanobacterium.
What is mutualism?
The regrowth of an ecosystem after a wildfire is an example of this type of succession.
What is secondary succession?
Organisms that occupy the third trophic level are usually classified as these.
What are secondary consumers?
Species that exert strong control on community structure due to their ecological roles, not necessarily abundance.
What are keystone species?
Only about 10% of energy is transferred from one trophic level to the next. The rest is primarily lost in this form.
What is heat?
This type of symbiotic relationship benefits one species and has no significant effect on the other.
What is commensalism?
In primary succession, these organisms are typically the pioneer species that colonize bare rock.
What are lichens and mosses?
A hawk that feeds on snakes, which eat mice that eat plants, is at this trophic level.
What is a tertiary or quaternary consumer?
Two species competing for the exact same niche cannot coexist indefinitely, according to this principle.
What is the competitive exclusion principle?
DAILY DOUBLE: In an energy pyramid, a trophic level with a large biomass but low individual size and high reproductive rate might be this level.
What is the primary producer level?
Identify the ecological consequence if mutualistic pollinators were removed from an ecosystem.
What is reduced plant reproduction, leading to cascading effects on food webs and biodiversity?
DAILY DOUBLE: Explain how species diversity typically changes over the course of succession.
What is: Species diversity tends to increase at first, stabilize, and then sometimes decrease as a few species become dominant in the climax community?
Explain why energy pyramids typically do not exceed four or five trophic levels.
What is: Because the energy available diminishes significantly with each transfer, limiting biomass and sustainability at higher levels?
Predict the outcome of removing a top predator from a stable food web.
What is: Trophic cascade resulting in overpopulation of prey and depletion of lower trophic levels (e.g., herbivores overgrazing producers)?
Explain why eating at lower trophic levels (e.g., consuming producers) is more energy efficient for human populations.
What is: Because less energy is lost through each trophic transfer, eating producers minimizes energy loss and maximizes caloric intake efficiency?
Describe a real-world example of parasitism that also involves manipulation of the host's behavior.
What is: The parasitic fungus Ophiocordyceps infects ants and alters their behavior to maximize spore dispersal?
Compare the roles of facilitation and inhibition in ecological succession.
What is: Facilitation occurs when early species prepare the environment for later species, while inhibition occurs when established species prevent others from colonizing?
Use ecological reasoning to explain what might happen to a food web if detritivores were removed.
What is: Nutrient cycling would halt, leading to a buildup of organic waste, depletion of soil nutrients, and collapse of primary productivity?
Justify how the introduction of an invasive species might decrease biodiversity in a native ecosystem.
What is: By outcompeting native species for resources, altering habitat structure, or introducing novel predators or pathogens, invasive species reduce native populations?