Animals
What is the term for an animal that is only active at night?
Nocturnal
Plant process using the sun, water, and CO₂ to make food?
Photosynthesis
What is the primary role of decomposer bacteria in an ecosystem?
Break down dead matter and recycle nutrients.
Which organism is a primary producer: a rabbit, a rose bush, or a decomposer bacteria?
Rose bush
What is the common term for the vital role of fungi and bacteria in breaking down dead plants and animals?
Decomposition
How do beavers, as a keystone species, change their ecosystem?
They build dams that create wetlands for other species.
Term for an organism that makes its own food?
Producer or Autotroph
Bacteria in the genus Rhizobium have a vital relationship with plants. What do they provide?
They fix nitrogen from the air for the plant.
What critical gas do plants and cyanobacteria produce that animals need to breathe?
Oxygen
What symbiotic relationship between fungi and plant roots greatly increases the plant's water and nutrient uptake?
Mycorrhizae
How do wolves in Yellowstone show a "trophic cascade"?
Wolves reduced elk, which allowed plants to recover, changing the entire ecosystem.
How does the "Edge Effect" harm deep-forest plants?
Creates drier, brighter conditions, shrinking their specialized habitat.
How can certain bacteria help clean up polluted groundwater, like at an old industrial site?
They perform bioremediation by consuming toxic chemicals.
What is the interconnected series of these feeding relationships called: plants are eaten by a grasshopper, which is eaten by a frog, which is eaten by a snake?
A food chain
Why is a crop rotation strategy that includes legumes beneficial for soil health without synthetic fertilizer?
Legumes host bacteria that fix nitrogen, enriching the soil.
Why are frogs bioindicators?
Their permeable skin absorbs pollutants, and they need both water and land to survive.
Name and benefit of a plant's symbiotic relationship with soil fungi?
Mycorrhizae; provides more water and nutrients.
In a wastewater treatment plant, why is the bacterial "activated sludge" stage so crucial?
Bacteria consume organic waste, purifying the water.
In the nitrogen cycle, what is the specific role of bacteria that live in root nodules of legumes?
Nitrogen fixation
How can the presence of specific saprotrophic fungi in soil act as a bioindicator for past land use, like old orchards?
They are specialists, decomposing only certain tree residues, revealing past flora.
How can losing one pollinator reduce genetic diversity and productivity?
It reduces plant reproduction, leading to smaller, less genetically diverse plant populations that capture less total energy.
Why is a "keystone" plant like a fig tree critical beyond its numbers?
It provides essential year-round food; its loss would cause widespread ecosystem collapse.
Why are cyanobacteria considered the most critical primary producers in open ocean ecosystems?
They are the base of the food web and produce most of the ocean's oxygen.
How does the reintroduction of a wolf population (animal) indirectly benefit a river's physical structure through plant growth?
Wolves reduce grazing animals, allowing plants to recover, which stabilizes riverbanks.
In sustainable agriculture, how does fungal-dominated compost differ from bacterial-dominated compost in its effect on long-term soil carbon and perennial crops?
Fungal compost builds stable, long-lasting soil carbon and supports perennial systems better.