What makes a species a keystone species?
It has a disproportionately large effect on ecosystem structure.
Which biome has low precipitation, extreme temperatures, and sparse vegetation?
Desert.
What does “non‑native”/invasive mean?
A species introduced outside its natural range.
What is one major cause of habitat destruction?
Deforestation, agriculture, mining, roads.
What process turns water vapor into clouds?
Condensation.
What defines a dominant species?
It makes up most of the biomass in an ecosystem
What is the main difference between freshwater and marine biomes?
Salinity.
Name one reason invasive species spread rapidly.
No natural predators.
What is habitat fragmentation?
Large habitats broken into smaller “islands.”
What process removes CO₂ from the atmosphere?
Photosynthesis.
Why do rare species often have low ecosystem impact?
They have low numbers and narrow ranges.
Which biome has four seasons and deciduous trees?
Temperate forest.
What is one way invasive species harm ecosystems?
Outcompete native species for resources.
What causes algal blooms in water ecosystems?
Fertilizer runoff.
Is a forest a carbon source or sink?
A carbon sink (absorbs more carbon than it releases).
What is one reason common species add stability to ecosystems?
They are widespread generalists that buffer against change.
What is the shallow, sunlight‑rich zone of a lake called?
Littoral zone.
What is one human‑led solution to invasive species?
Habitat restoration, removal, native gardens, education.
What happens when species are removed faster than they can reproduce?
Population crash.
What gas do animals release during respiration?
Carbon dioxide.
Which category (KDRC map) would a beaver belong to?
Keystone species (ecosystem engineer).
Why do high‑diversity biomes tend to be more stable?
More species = more resilience to change.
Why do invasive species often become dominant species?
They are generalists and reproduce quickly.
What gases contribute to the greenhouse effect?
CO₂ and methane.
Why does burning fossil fuels increase atmospheric carbon?
It releases stored carbon back into the atmosphere.