Producers, Consumers, Decomposers
This group makes their own food using sunlight and are the primary source of energy for most ecosystems
Producers (autotrophs), e.g., green plants, algae; use sunlight in photosynthesis.
One nonliving factor that affects all ecosystems and is required for plant growth.
Water (or sunlight, soil nutrients, temperature)
The term for the variety of living species in an ecosystem, including plants, animals, and microorganisms
Biodiversity: the variety of living species in an ecosystem, including plants, animals, and microorganisms
The process by which plants take in carbon dioxide and convert it into organic molecules
Photosynthesis.
The gas produced by plants during photosynthesis that animals need to breathe.
Oxygen (O2)
An organism that obtains energy by eating other organisms; includes herbivores, carnivores, and omnivores.
Consumers (heterotrophs); examples: deer (herbivore), wolf (carnivore), raccoon (omnivore).
List two biotic factors that can limit a population’s size.
Predation, disease, competition, availability of mates, presence of predators or competitors
One reason biodiversity is important for ecosystem resilience after a disturbance.
Increased species diversity allows ecosystems to maintain function after disturbances because different species can perform similar roles.
One human activity that increases atmospheric carbon dioxide
Burning fossil fuels (combustion), deforestation.
Describe the overall purpose of cellular respiration in cells
to release energy from glucose to produce ATP for cellular processes
These organisms break down dead material, returning nutrients to the soil and completing nutrient cycles.
Decomposers (fungi, bacteria, detritivores) break down dead matter releasing nutrients.
Explain how a decrease in water availability might affect population size of a freshwater frog species (include at least two direct effects)
Less water → fewer breeding sites, higher mortality, reduced food resources → population decline; may force migration.
Describe how invasive species can reduce biodiversity and give one NC-specific example.
Invasive species outcompete native species, reduce habitat quality, and alter food webs. NC example: lionfish in coastal waters or cogongrass in terrestrial habitats (note local relevance depending on region).
Describe two ways carbon returns to the atmosphere from living organisms.
Respiration by organisms, decomposition of dead organisms, combustion of organic matter.
Identify one similarity and one difference between photosynthesis and cellular respiration
Similarity: Both involve electron transfer and use membranes/enzymes; Difference: Photosynthesis stores energy (builds glucose) using light; respiration releases energy by breaking down glucose
Name the type of consumer that eats only plants, and give one example appropriate to a forest ecosystem
Herbivore; example: white-tailed deer in a forest.
Describe how shelter and space together influence competition among territorial animals; give a specific animal example.
Limited shelter/space increases fights and territory defense (example: nesting territories in peregrine falcons), leading to exclusion of subordinates and reduced local density.
Explain how habitats impact diversity and population survival; include one human impact on ecosystems.
Fragmentation isolates populations, reducing gene flow and increasing inbreeding risk, which lowers adaptive potential. Human activity example: road building or urban development
Explain the role of decomposers in the carbon cycle
Decomposers break down dead organic matter, releasing carbon dioxide and returning carbon to soil and atmosphere
Explain why both plants and animals perform cellular respiration even though only plants photosynthesize
Plants need ATP for maintenance and growth, so they respire to use the glucose they made; animals must respire because they cannot photosynthesize to make glucose
Explain how producers, consumers, and decomposers interact in a simple food chain and identify one positive and one negative consequence of those interactions (use terms: coexistence, competition).
Example answer: Producers make organic matter; consumers eat producers or other consumers; decomposers break down waste. Positive: coexistence—pollinators and flowering plants benefit both; Negative: competition—two predators competing for same prey can reduce population numbers.
Give an example of how changing one abiotic factor affects population growth of a small organism
Example: Use fast-growing algae in aquarium tanks; manipulate nutrient concentration (abiotic); control: normal nutrient level; variable: increased nitrate; measure algal population growth over 2 weeks; expect higher nitrate → rapid algal growth then possible collapse due to oxygen depletion.
Propose a short schoolyard project (one paragraph) to improve local biodiversity, including steps, expected outcomes, and how you would measure success.
Example project: Create native pollinator garden with diverse native plants, remove invasive species, install signage. Steps: survey baseline species, plant native mix, monitor pollinator visits and plant survival for one season. Expected outcomes: increased pollinator sightings and native plant cover. Measure success: species count, percent cover, photo records.
Using the terms photosynthesis, respiration, fossil fuels, and decomposition, summarize how carbon moves through the biosphere, atmosphere, and geosphere.
Photosynthesis removes CO2 from atmosphere into plant biomass; organisms respire returning CO2; decomposition and fossil fuel combustion release stored carbon back to atmosphere; some carbon becomes fossil fuels in geosphere over long time.
Describe how photosynthesis and cellular respiration together support the flow of energy and cycling of matter in an ecosystem; include where the energy comes from and how molecules are transformed.
Photosynthesis captures solar energy to build organic molecules (glucose). Cellular respiration breaks these molecules to release energy (ATP) and returns CO2 and water to the environment. Energy input is sunlight; matter cycles (C, H, O) between organisms and environment.