Biodiversity and Populations
What term describes the maximum number of individuals an environment can sustainably support?
Carrying Capacity
In an energy pyramid, which trophic level contains the most energy and organisms?
Producers/Autotrophs
What biogeochemical cycle involves nitrogen-fixing bacteria converting atmospheric nitrogen into usable form.
Nitrogen Cycle
Which gas is most associated with climate change due to fossil fuel combustion?
Carbon Dioxide
What environmental factor limits the range of an organism that cannot tolerate acidic soils?
What is pH
A sharp decrease in sea otter populations led to a boom in sea urchins, which overgrazed kelp forests. What role did the sea otter play in this ecosystem?
Keystone Species
Why is only about 10% of the energy transferred from one trophic level to the next?
The rest of the energy is lost as heat, used for metabolism, or not all biomass is consumed.
In which cycle do plants take in CO₂ and release O₂, while animals release CO₂ and take in the oxygen.
Carbon Cycle
Give an example of a sustainable solution to reduce habitat destruction.
Creating wildlife corridors or enforcing land-use zoning laws.)
How might prolonged drought affect a population of amphibians?
Reduced breeding sites and moisture, leading to population decline.
Explain how density-dependent limiting factors can regulate population growth. Give an example.
There is greater impact with population density, e.g., disease spreads more easily in dense populations.)
Create an energy pyramid using the following. Arrange the following in order of energy flow: primary consumer, decomposer, secondary consumer, producer
Producer → Primary Consumer → Secondary Consumer → Decomposer)
How does phosphorus enter the food web if it is not found in the atmosphere?
Through weathering of rocks into soil and water, then absorbed by plants.)
How can introducing non-native species disrupt an ecosystem? (A: They may outcompete or prey on native species, altering population dynamics.)
They may outcompete or prey on native species, altering population dynamics.)
Explain how fire-adapted species survive and thrive after wildfires. (A: Some have fire-resistant seeds or need fire to germinate; others resprout quickly.)
Some have fire-resistant seeds or need fire to germinate; others resprout quickly.)
Which type of graph best models' logistic population growth and why?
S curve; An S-shaped curve; it shows initial growth, slowing, and leveling up due to carrying capacity.
Compare the energy available to a tertiary consumer with that of a herbivore in the same ecosystem.
Tertiary consumers get significantly less energy due to multiple energy transfers
Compare how oxygen and carbon cycle through photosynthesis and respiration. (A: Photosynthesis uses CO₂ and releases O₂; respiration uses O₂ and releases CO₂.)
Photosynthesis uses CO₂ and releases O₂; respiration uses O₂ and releases CO₂.
Describe a real-world solution to reduce the effects of agricultural runoff on aquatic ecosystems.
Drip Irrigation
Apply the exact amount of fertilizer (less excess)
Buffer zones -plant vegetation to filter pollutants and reduce runoff.
Crop rotation
Describe how tolerance ranges determine where a species can live. Give an example involving temperature.
Species can only survive within specific environmental limits; e.g., coral bleaching occurs outside narrow temp range.
Describe two ways invasive species can disrupt biodiversity and ecosystem balance.
Outcompete native species for resources; alter food webs or introduce new diseases.
Explain how energy flow differs between a food chain and a food web. Why is a web a better model?
Food webs show multiple feeding relationships and are more accurate representations of energy flow
Process in which bacteria in the soil convert Nitrogen into compound forms that organisms can use.
Nitrogen Fixation
A wetland ecosystem is drained for development. Construct an argument predicting the potential long-term impacts on local biodiversity, nutrient cycling, and population dynamics.
Loss of habitat leads to species decline and reduced biodiversity.
Disruption of nutrient cycling, especially nitrogen and phosphorus.
Altered population dynamics due to loss of keystone species or introduction of edge species.
Long-term ecosystem instability or collapse.
Adaptations plants have for winter.
Flexible branches
Waxy needles