Resource Availability
What are two abiotic resources organisms need to survive? (name two)
Examples: water, sunlight (also: soil nutrients, oxygen, rainfall).
What is competition?
Competition: when individuals/populations use the same limited resource (example: deer competing for limited plants in winter).
What is a producer? Give one example.
Producer: organism that makes its own food (autotroph), e.g., plants or algae.
Define biodiversity in one sentence.
Biodiversity: the variety of life (species) in an area or ecosystem.
Name two weather hazards
Examples: tornadoes, floods, hurricanes, droughts, blizzards.
Define carrying capacity in one sentence.
The carrying capacity is the maximum population size of a species that an environment can sustain given its available biotic and abiotic resources.
Explain how an increase in hyena population might affect lion population (predator/competitor interaction).
Hyenas increase → more competition for prey and/or scavenged food → lions may have reduced food, lower survival/reproduction; could lead to decreased lion numbers or altered behavior.
write one clear sentence that explains the direction of energy flow through an ecosystem.
Energy flows Sun → Producers → Consumers (energy moves in one direction through food chains).
Why does higher biodiversity help an ecosystem recover from disturbance?
More species means more ways to fill roles after disturbance; other species can replace lost functions, speeding recovery.
What precursor conditions help form tornadoes? (two items)
Warm, moist air colliding with cooler, drier air; wind shear (winds at different altitudes blowing at different speeds/directions).
Give one example from the materials of how humans can reduce resource availability for wildlife.
Example: withdrawing irrigation water from a stream reduces water for wildlife; development removes habitat.
Define mutualism and give the alligator–finch example in one sentence.
Mutualism: both benefit; example: small finch eats food from alligator’s teeth while alligator gets cleaning.
How would an increase in a herbivore population likely affect its predator population? Explain the relationship.
More herbivores → more food for predators → predator population may increase; if herbivores overconsume plants, plant populations may decrease and then predator numbers could later drop.
Give two human activities listed that reduce habitat and biodiversity.
Examples: clear-cutting forests for development, building roads/cities, overfishing, oil drilling that destroys habitats.
Explain why tsunami risk is linked to earthquakes and one monitoring method scientists use.
Undersea earthquakes/landslides can displace water to form tsunamis; scientists monitor seismic activity and ocean sensors/buoys to detect tsunamis.
Explain why oxygen can be a limiting abiotic resource in a lake and one effect on fish populations.
Low dissolved oxygen (e.g., from eutrophication or warming) stresses fish, reduces health, and can cause population decline or fish kills.
Contrast commensalism and parasitism with one example of each
Commensalism benefits one without affecting the other (moss on tree). Parasitism benefits one and harms the host (fleas on a dog).
Define exponential population growth and name one condition that can lead to it.
Exponential growth: population increases by a constant factor repeatedly (J-shaped curve), often when resources are abundant.
Explain succession: name a pioneer species example and one process that follows.
Succession: pioneer species (lichens) colonize bare rock → soil forms → grasses and shrubs → mature community (trees).
Name two ways scientists monitor volcanoes and what each detects (brief).
Seismometers detect ground vibrations (earthquakes); GPS/tiltmeters detect ground deformation (magma movement); gas sensors measure volcanic gas emissions; thermal imaging detects heat changes.
Describe how an algal bloom forms from human activity and name one ecosystem effect.
Fertilizer runoff increases nutrients in water → algal bloom → depleted oxygen when algae die → harm to aquatic life.
Describe how invasive (introduced) species can change carrying capacity and biodiversity in a habitat.
Introduced species can outcompete natives for resources, lowering native populations and reducing carrying capacity for native species; biodiversity drops.
Explain how loss of a keystone prey species could affect a food web (two consequences).
Loss of keystone prey can cause predators to decline, competing species may shift diets, and overall food-web structure can collapse or reorganize.
Describe how overharvesting (use the bison or cod example) can reduce genetic diversity and long-term population recovery.
Overharvesting reduces population size and removes alleles from the gene pool, lowering genetic diversity and reducing ability to adapt — recovery is slower and risk of extinction increases.
Using the Enhanced Fujita Scale idea: describe how scientists use historical data to assess tornado risk in a region.
Scientists analyze past tornado locations, frequency, and intensity; they combine historical records with climate and topography to create risk maps and inform warnings.