A Within genes, among species, and among ecosystems
B Only in the climate
C Only among animals
D Only in soil minerals
Answer: A. Within genes, among species, and among ecosystems. Biodiversity includes genetic diversity, species diversity, and ecosystem diversity.
Genetic diversity is variation in:
A Habitats only
B Alleles and genes within or among populations
C Species body size only
D Weather patterns
Answer: B. Alleles and genes within or among populations. Genetic diversity describes variation in genetic material within and among populations.
Species richness is a measure of:
A The number of individuals only
B The average size of organisms
C The number of species in a defined area
D The number of ecosystems on Earth
Answer: C. The number of species in a defined area. Species richness is the count of distinct species present in a particular place.
Species evenness describes:
A How many habitats occur
B The genetic distance between two species
C The number of individuals total
D How evenly individuals are distributed among species
Answer: D. How evenly individuals are distributed among species. Evenness describes the relative abundance distribution among species in a community.
An endemic species is naturally found:
A Only within a particular geographic region
B Everywhere on Earth
C Only in captivity
D Only in the fossil record
Answer: A. Only within a particular geographic region. An endemic species has a naturally restricted range limited to a particular place or region.
A native species is one that:
A Was recently introduced by people
B Occurs naturally in a region without human introduction
C Is always endangered
D Has no predators
Answer: B. Occurs naturally in a region without human introduction. A native species is part of a region’s natural biota, rather than introduced from elsewhere by people.
Global extinction means that:
A A species leaves one forest
B A species becomes rare
C No living individuals of the species remain anywhere
D A population moves to another region
Answer: C. No living individuals of the species remain anywhere. Global extinction occurs when the last living individual of a species is gone.
Extirpation is:
A The origin of a new species
B A temporary seasonal decline
C A population increasing in a reserve
D The disappearance of a species from a particular region while it survives elsewhere
Answer: D. The disappearance of a species from a particular region while it survives elsewhere. Extirpation is local extinction from one area, not global extinction of the species.
Habitat loss threatens biodiversity mainly because it:
A Reduces resources and suitable places for organisms to live and reproduce
B Increases every population
C Creates unlimited migration routes
D Prevents all competition
Answer: A. Reduces resources and suitable places for organisms to live and reproduce. Habitat loss reduces the area and quality of resources available to species.
Habitat fragmentation occurs when:
A A habitat becomes larger
B A continuous habitat is broken into smaller separated patches
C A species develops a new trait
D An ecosystem gains more rainfall
Answer: B. A continuous habitat is broken into smaller separated patches. Fragmentation divides continuous habitat into smaller, often isolated patches.
An invasive species is generally a nonnative organism that:
A Cannot spread
B Has no ecological impact
C Establishes and causes or is likely to cause harm
D Is always endangered
Answer: C. Establishes and causes or is likely to cause harm. Invasive species establish outside their native range and cause or are likely to cause harm.
Overexploitation reduces biodiversity when:
A A species is protected
B A species migrates naturally
C Harvest is below replacement
D Organisms are removed faster than populations can replace them
Answer: D. Organisms are removed faster than populations can replace them. Unsustainable harvest can cause population decline when removals exceed natural replacement.
How can climate change affect biodiversity?
A It can shift suitable ranges and alter the timing of biological events
B It stops all evolution
C It affects only rocks
D It prevents species from interacting
Answer: A. It can shift suitable ranges and alter the timing of biological events. Climate shifts can change where species can live and when they migrate, flower, breed, or feed.
Pollinators support biodiversity by:
A Breaking down rocks
B Helping many plants reproduce
C Creating nitrogen gas
D Preventing all seed dispersal
Answer: B. Helping many plants reproduce. Pollinators transfer pollen and support reproduction in many wild plants and crops.
Conserving a species in its natural ecosystem is called:
A Ex situ conservation
B Captive management
C In situ conservation
D Cryopreservation
Answer: C. In situ conservation. In situ conservation protects species within their natural habitats and ecosystems.
Captive breeding and seed banks are examples of:
A In situ conservation
B Natural succession
C Habitat corridors
D Ex situ conservation
Answer: D. Ex situ conservation. Ex situ conservation maintains species or genetic material outside its natural habitat.
A seed bank helps conserve plant diversity by:
A Storing seeds for future propagation or research
B Removing seeds from all ecosystems
C Preventing plants from evolving
D Replacing all natural habitats
Answer: A. Storing seeds for future propagation or research. Seed banks preserve living seed collections that can support restoration, research, and genetic conservation.
A wildlife corridor is intended to:
A Separate all populations permanently
B Connect habitats and support movement between them
C Remove all edge effects
D Replace every protected area
Answer: B. Connect habitats and support movement between them. Corridors connect habitat patches and can facilitate dispersal and gene flow.
A keystone species has:
A The largest body in a community
B The greatest lifespan
C An ecological effect disproportionately large relative to its abundance
D No effect on other species
Answer: C. An ecological effect disproportionately large relative to its abundance. Keystone species exert outsized effects on community structure relative to their abundance.
A flagship species is often used to:
A Measure soil pH
B Represent all species scientifically
C Eliminate the need for habitat protection
D Build public interest and support for conservation
Answer: D. Build public interest and support for conservation. Flagship species help communicate conservation goals and attract public support.
Protecting an umbrella species may help conserve other species because:
A Its habitat requirements can cover a large area used by many species
B It is always the rarest species
C It has no habitat needs
D It lives only in captivity
Answer: A. Its habitat requirements can cover a large area used by many species. Protecting broad habitat required by an umbrella species may also protect other organisms in that landscape.
An indicator species can be used to:
A Predict the exact future of every ecosystem
B Signal environmental conditions through its response
C Replace all biodiversity surveys
D Create new habitats
Answer: B. Signal environmental conditions through its response. Indicator species respond to selected environmental conditions and can help monitor ecological change.
Functional diversity refers to variation in species’:
A Names only
B Geographic locations only
C Ecological traits and roles
D Age classes only
Answer: C. Ecological traits and roles. Functional diversity describes variation in ecological traits and roles within a community.
A protected area is established primarily to:
A Allow any land use without limits
B Remove all native species
C Increase habitat fragmentation
D Safeguard important habitats, species, or ecological processes
Answer: D. Safeguard important habitats, species, or ecological processes. Protected areas conserve biodiversity and ecological features through management or legal safeguards.
Ecological restoration aims to:
A Assist recovery of degraded ecosystems and their functions
B Make all ecosystems identical
C Remove every disturbance
D Stop nutrient cycling
Answer: A. Assist recovery of degraded ecosystems and their functions. Restoration supports recovery of ecosystem structure, species, and processes after degradation.
At one site, what does alpha diversity measure?
A Diversity within one community
B Differences among continents
C Variation within one gene
D Total global species count
Answer: A. Diversity within one community. Alpha diversity describes diversity within a local community or site.
How does beta diversity compare communities?
A Total diversity across a continent
B Species turnover between sites
C Genetic variation within individuals
D Species count at one site
Answer: B. Species turnover between sites. Beta diversity describes differences in species composition between communities or sites.
Across a region, what does gamma diversity describe?
A Variation among individuals
B Abundance of one species
C Total diversity across a region
D Diversity within one plot
Answer: C. Total diversity across a region. Gamma diversity summarizes diversity across a broader region or landscape.
In a small isolated population, what can genetic drift cause?
A Immediate formation of new species
B Guaranteed population growth
C Increased habitat connectivity
D Rapid loss of genetic variation
Answer: D. Rapid loss of genetic variation. Random changes in allele frequencies can remove genetic variation, especially in small populations.
After a severe population bottleneck, what often declines?
A Genetic variation
B Food web length
C Species evenness
D Habitat productivity
Answer: A. Genetic variation. A sharp population reduction can leave fewer alleles in the surviving population.
Why can inbreeding increase vulnerability?
A Population size rises automatically
B Harmful recessive alleles may surface
C Mutations stop occurring
D All traits become beneficial
Answer: B. Harmful recessive alleles may surface. Inbreeding increases the chance that harmful recessive variants are expressed.
How does genetic diversity support adaptation?
A Prevents every mutation
B Keeps populations genetically identical
C Provides variation for natural selection
D Stops environmental change
Answer: C. Provides variation for natural selection. Genetic variation gives natural selection more traits to act on as conditions change.
What changes near edges of fragmented forests?
A Soil minerals disappear instantly
B Planetary orbit and tides
C Genetic codes of all species
D Microclimate and exposure patterns
Answer: D. Microclimate and exposure patterns. Forest edges can experience altered light, temperature, wind, humidity, and disturbance.
When a host species disappears, what may happen to its obligate parasite?
A Co-extinction
B Ecological succession
C Range expansion
D Convergent evolution
Answer: A. Co-extinction. A parasite that depends on one host may also disappear if that host becomes extinct.
Why repeat biodiversity surveys in the same area?
A Guarantee species recovery
B Track change over time
C Replace legal protection
D Predict every future threat
Answer: B. Track change over time. Repeated surveys help reveal changes in species presence or abundance over time.
How does a biodiversity baseline aid conservation planning?
A Predicts every future threat
B Guarantees species recovery
C Provides a reference for comparison
D Replaces legal protection
Answer: C. Provides a reference for comparison. Baseline records provide a starting point for comparing future ecological change.
What does environmental DNA sampling detect?
A Weather satellites alone
B Fossilized footprints only
C Whole adult specimens
D Genetic traces in samples
Answer: D. Genetic traces in samples. Environmental DNA methods detect genetic material organisms leave in water, soil, or other samples.
Which IUCN categories indicate threatened status?
A Vulnerable, Endangered, Critically Endangered
B Least Concern, Data Deficient
C Near Threatened, Least Concern
D Extinct, Data Deficient, Least Concern
Answer: A. Vulnerable, Endangered, Critically Endangered. The IUCN Red List treats Vulnerable, Endangered, and Critically Endangered as threatened categories.
If a species is Data Deficient, what does that mean?
A The population is increasing rapidly
B Available evidence is insufficient
C The species is definitely safe
D Extinction has already occurred
Answer: B. Available evidence is insufficient. Data Deficient means evidence is inadequate to assess extinction risk; it does not mean the species is safe.
Which international agreement regulates trade in listed wild species?
A Ramsar Convention
B Montreal Protocol
C CITES
D Convention on Biological Diversity
Answer: C. CITES. CITES uses permits and certificates to regulate international trade in listed wild animal and plant specimens.
Why can bycatch reduce marine biodiversity?
A Only target species are counted
B Marine habitats become protected
C Species gain new breeding grounds
D Non-target species are captured
Answer: D. Non-target species are captured. Bycatch unintentionally captures non-target organisms, which can contribute to population declines.
What can nutrient runoff cause in lakes?
A Algal blooms and oxygen depletion
B More coral reef formation
C Higher oxygen and clearer water
D No change in water chemistry
Answer: A. Algal blooms and oxygen depletion. Excess nutrients can fuel algal blooms; decomposition may then reduce dissolved oxygen.
How do ecological networks support isolated populations?
A Eliminate genetic variation
B Enable dispersal and gene flow
C Stop habitat succession
D Prevent all natural movement
Answer: B. Enable dispersal and gene flow. Connected habitats allow organisms to move, helping maintain gene flow among populations.
What does the Red List Index track?
A Annual rainfall totals
B Number of protected parks
C Trends in extinction risk
D Total cultivated crop varieties
Answer: C. Trends in extinction risk. The Red List Index summarizes trends in extinction risk across assessed species.
Why include local and Indigenous knowledge in conservation?
A Guarantees consensus
B Removes all management uncertainty
C Replaces ecological monitoring
D Adds place-based ecological insight
Answer: D. Adds place-based ecological insight. Local and Indigenous knowledge can add long-term, place-specific observations to conservation decisions.
What does sustainable use of biodiversity require?
A Use without long-term depletion
B Permanent exclusion of people
C Use regardless of recovery
D Maximum harvest in one year
Answer: A. Use without long-term depletion. Sustainable use avoids long-term decline in biological diversity while allowing its use.
How can ecosystem services connect biodiversity with human well-being?
A Species names replace ecosystems
B Nature’s benefits support people
C Human needs have no link
D Only recreation matters
Answer: B. Nature’s benefits support people. Biodiversity underpins ecosystem functions and benefits people receive, including food, clean water, and pollination.
What helps a conservation area remain effective over time?
A No monitoring or enforcement
B Boundary maps alone
C Management matched to local threats
D Visitor numbers only
Answer: C. Management matched to local threats. Effective areas need management that responds to local pressures and changing conditions.
How do crop-variety mixtures benefit agricultural biodiversity?
A Rely on one seed line
B Reduce seed-saving practices
C Remove local crop varieties
D Maintain more genetic variation
Answer: D. Maintain more genetic variation. Growing diverse varieties helps conserve genetic resources within cultivated plants.
Why should conservation actions be evaluated regularly?
A Keep every action unchanged
B Adapt management using new evidence
C Avoid comparing results
D Remove community input
Answer: B. Adapt management using new evidence. Evaluation shows whether actions are working and supports adaptive management.