Biology Flashcards: Model Human Activity Biodiversity Effects

What this deck covers

This deck focuses on Model Human Activity Biodiversity Effects, giving you a quick way to review the definitions, rules, and examples that matter most for Biology.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: What is biodiversity, as used in ecology when modeling human impacts on ecosystems?

Answer: Variety of life at genetic, species, and ecosystem levels. Encompasses all levels from genes to entire ecosystems.

Flashcard 2: What is the typical biodiversity effect of road building through habitat?

Answer: Fragmentation, edge effects, and higher mortality; diversity declines. Roads create barriers and increase wildlife-vehicle collisions.

Flashcard 3: Identify the predicted effect on $S$ in $S=cA^z$ when habitat area $A$ decreases.

Answer: Species richness $S$ decreases. Smaller areas support fewer species according to the model.

Flashcard 4: What is the species–area relationship formula used in biodiversity modeling?

Answer: $S=cA^z$. Mathematical relationship between habitat size and species count.

Flashcard 5: What is selective logging, and how does it differ from clear-cutting in impact?

Answer: Removes some trees; typically less severe than clear-cutting. Maintains canopy cover and some habitat structure.

Flashcard 6: What is pollution, and how can it reduce biodiversity in aquatic ecosystems?

Answer: Contaminants cause toxicity and habitat degradation; diversity declines. Toxins directly kill organisms and degrade water quality.

Flashcard 7: What is overexploitation, and what is its direct effect on biodiversity?

Answer: Harvesting faster than replacement; reduces populations and diversity. Taking more than natural reproduction can replenish.

Flashcard 8: What is the extinction rate, in the context of modeling human impacts?

Answer: Rate at which species disappear from a region or globally. Measures how quickly species are being lost permanently.

Flashcard 9: What is pollution, and how can it reduce biodiversity in aquatic ecosystems?

Answer: Contaminants cause toxicity and habitat degradation; diversity declines. Toxins directly kill organisms and degrade water quality.

Flashcard 10: What is genetic diversity, and why is it important for biodiversity under human change?

Answer: Variation in alleles; increases adaptability and resilience. More genetic variation provides better response to environmental changes.

Flashcard 11: What is desertification, and how can it affect biodiversity in drylands?

Answer: Land degradation to arid conditions; reduces productivity and diversity. Lower rainfall and plant growth support fewer species.

Flashcard 12: What is sustainable harvest, and how does it relate to population growth rate?

Answer: Harvest at or below replacement; does not exceed population growth. Harvest rate matches or stays below natural population increase.

Flashcard 13: What is biomagnification, and why does it threaten top predators?

Answer: Toxin concentration increases up food chains; harms apex species. Each trophic level multiplies toxin concentration from the level below.

Flashcard 14: What is biomagnification, and why does it threaten top predators?

Answer: Toxin concentration increases up food chains; harms apex species. Each trophic level multiplies toxin concentration from the level below.

Flashcard 15: What is species evenness in a community biodiversity model?

Answer: How evenly individuals are distributed among species. Measures if species have similar or unequal abundances.

Flashcard 16: What is ecosystem diversity in the context of biodiversity modeling?

Answer: Variety of habitats and ecological processes in a region. Includes diversity of community types and ecological functions.

Flashcard 17: What is ecological succession, and how can human disturbance alter it?

Answer: Community change over time; disturbance can reset to early stages. Major disturbances restart the process from pioneer species.

Flashcard 18: What is ocean acidification, and what organisms are especially impacted?

Answer: Lower ocean pH from $CO_2$; harms corals and shell-formers. Dissolved $CO_2$ makes seawater acidic, dissolving calcium structures.

Flashcard 19: Which option best describes a point-source pollutant affecting biodiversity?

Answer: A single identifiable discharge location (for example, a pipe). Single source makes pollution easier to identify and control.

Flashcard 20: What is a biodiversity hotspot, and why is it prioritized for conservation?

Answer: High endemism and high threat; protects many unique species. Conservation efforts here protect maximum species per unit effort.

Flashcard 21: What is desertification, and how can it affect biodiversity in drylands?

Answer: Land degradation to arid conditions; reduces productivity and diversity. Lower rainfall and plant growth support fewer species.

Flashcard 22: What is a wildlife corridor, and what biodiversity problem does it address?

Answer: Habitat link between patches; reduces isolation and boosts gene flow. Connects isolated patches to allow movement and breeding.

Flashcard 23: What is edge effect in fragmented habitats?

Answer: Altered conditions at habitat edges that change species survival. Edges have different light, temperature, and wind patterns.

Flashcard 24: What is carrying capacity $K$, and how can habitat degradation change $K$?

Answer: $K$ is max sustainable population; degradation lowers $K$. Reduced resources support fewer individuals in the population.

Flashcard 25: What is an endemic species, and why is it vulnerable to habitat loss?

Answer: Species restricted to one area; limited range increases extinction risk. Cannot escape to other areas when local habitat is destroyed.

Flashcard 26: What is bycatch, and how does it affect biodiversity?

Answer: Non-target capture; increases mortality of many species. Accidental capture kills species that aren't being targeted.

Flashcard 27: Identify the likely biodiversity trend when a habitat is restored and native plants re-established.

Answer: Species richness and evenness generally increase over time. Restoration removes human stressors and allows natural recovery.

Flashcard 28: What is a trophic cascade, often triggered by human removal of predators?

Answer: Food-web changes across trophic levels after predator loss. Effects ripple down from top predators to primary producers.

Flashcard 29: What does the exponent $z$ represent in the species–area model $S=cA^z$?

Answer: How strongly richness increases with area (slope on log-log plot). Higher $z$ values mean richness drops faster with area loss.

Flashcard 30: What is the typical biodiversity effect of road building through habitat?

Answer: Fragmentation, edge effects, and higher mortality; diversity declines. Roads create barriers and increase wildlife-vehicle collisions.

Flashcard 31: What is edge effect in fragmented habitats?

Answer: Altered conditions at habitat edges that change species survival. Edges have different light, temperature, and wind patterns.

Flashcard 32: What is overfishing, and what is a common community-level consequence?

Answer: Excess fish harvest; food-web shifts and reduced diversity. Removes key species and disrupts predator-prey relationships.

Flashcard 33: Identify the likely biodiversity trend when a habitat is restored and native plants re-established.

Answer: Species richness and evenness generally increase over time. Restoration removes human stressors and allows natural recovery.

Flashcard 34: Which option best describes a nonpoint-source pollutant affecting biodiversity?

Answer: Diffuse runoff from many locations (for example, farms and streets). Scattered sources make pollution harder to track and regulate.

Flashcard 35: Identify the predicted effect on $S$ in $S=cA^z$ when habitat area $A$ decreases.

Answer: Species richness $S$ decreases. Smaller areas support fewer species according to the model.

Flashcard 36: What is overexploitation, and what is its direct effect on biodiversity?

Answer: Harvesting faster than replacement; reduces populations and diversity. Taking more than natural reproduction can replenish.

Flashcard 37: What is climate change, and what is a common biodiversity outcome?

Answer: Long-term warming and shifts; range shifts and extinctions increase. Changing temperatures force species to migrate or face extinction.

Flashcard 38: What is bycatch, and how does it affect biodiversity?

Answer: Non-target capture; increases mortality of many species. Accidental capture kills species that aren't being targeted.

Flashcard 39: What is the extinction rate, in the context of modeling human impacts?

Answer: Rate at which species disappear from a region or globally. Measures how quickly species are being lost permanently.

Flashcard 40: What is ecosystem diversity in the context of biodiversity modeling?

Answer: Variety of habitats and ecological processes in a region. Includes diversity of community types and ecological functions.

Flashcard 41: What is thermal pollution, and what is its typical effect on dissolved oxygen?

Answer: Warmer water from discharge; dissolved oxygen decreases. Warm water holds less dissolved oxygen than cool water.

Flashcard 42: What is the species–area relationship formula used in biodiversity modeling?

Answer: $S=cA^z$. Mathematical relationship between habitat size and species count.

Flashcard 43: What is species richness in a community biodiversity model?

Answer: The number of different species present. Total count of different species, regardless of abundance.

Flashcard 44: What is sustainable harvest, and how does it relate to population growth rate?

Answer: Harvest at or below replacement; does not exceed population growth. Harvest rate matches or stays below natural population increase.

Flashcard 45: What is selective logging, and how does it differ from clear-cutting in impact?

Answer: Removes some trees; typically less severe than clear-cutting. Maintains canopy cover and some habitat structure.

Flashcard 46: What is deforestation, and what is its immediate effect on forest biodiversity?

Answer: Forest removal; rapid declines in habitat specialists and richness. Forest-adapted species lose habitat and cannot survive elsewhere.

Flashcard 47: Which option best describes a point-source pollutant affecting biodiversity?

Answer: A single identifiable discharge location (for example, a pipe). Single source makes pollution easier to identify and control.

Flashcard 48: What is the greenhouse effect, and why does human-enhanced $CO_2$ matter for biodiversity?

Answer: Atmospheric heat trapping; added $CO_2$ drives warming and range shifts. Enhanced greenhouse effect accelerates climate change impacts.

Flashcard 49: What is bioindicator evidence that acid rain is reducing freshwater biodiversity?

Answer: Declines in sensitive species such as mayflies and some fish. Acid-sensitive species disappear first as pH decreases.

Flashcard 50: What is inbreeding depression in conservation biology?

Answer: Reduced fitness from mating among relatives and harmful recessives. Related individuals share more harmful recessive alleles.

Flashcard 51: What is habitat loss, and how does it typically affect biodiversity?

Answer: Destruction of habitat; usually decreases biodiversity. Removes living space and resources species need to survive.

Flashcard 52: What is an invasive species in models of human-caused biodiversity change?

Answer: Non-native species that spreads and harms native communities. Outcompetes natives and lacks natural predators or diseases.

Flashcard 53: What is bioaccumulation in an organism exposed to pollutants?

Answer: Toxins build up in tissues over time faster than elimination. Organism cannot eliminate toxins as fast as they enter.

Flashcard 54: What is an indicator species, and how is it used to infer biodiversity change?

Answer: Species sensitive to change; signals ecosystem health and diversity. Changes in these species reflect broader ecosystem condition.

Flashcard 55: What is bioaccumulation in an organism exposed to pollutants?

Answer: Toxins build up in tissues over time faster than elimination. Organism cannot eliminate toxins as fast as they enter.

Flashcard 56: What is deforestation, and what is its immediate effect on forest biodiversity?

Answer: Forest removal; rapid declines in habitat specialists and richness. Forest-adapted species lose habitat and cannot survive elsewhere.

Flashcard 57: What is habitat fragmentation, and what is its typical biodiversity effect?

Answer: Breaking habitat into isolated patches; lowers biodiversity. Small isolated patches support fewer species than large areas.

Flashcard 58: What is the primary biodiversity effect of converting forest to monoculture cropland?

Answer: Lower species richness and evenness due to habitat simplification. Monocultures eliminate habitat complexity and food sources.

Flashcard 59: What is the typical biodiversity effect of urbanization on native species?

Answer: Decreases native diversity; favors generalists and invasives. Urban environments favor adaptable species over specialists.

Flashcard 60: What is climate change, and what is a common biodiversity outcome?

Answer: Long-term warming and shifts; range shifts and extinctions increase. Changing temperatures force species to migrate or face extinction.

Flashcard 61: What is genetic drift, and why is it stronger in small human-isolated populations?

Answer: Random allele frequency change; stronger when population size is small. Random sampling effects are proportionally larger in small populations.

Flashcard 62: What is habitat fragmentation, and what is its typical biodiversity effect?

Answer: Breaking habitat into isolated patches; lowers biodiversity. Small isolated patches support fewer species than large areas.

Flashcard 63: What is ecological succession, and how can human disturbance alter it?

Answer: Community change over time; disturbance can reset to early stages. Major disturbances restart the process from pioneer species.

Flashcard 64: What is species richness in a community biodiversity model?

Answer: The number of different species present. Total count of different species, regardless of abundance.

Flashcard 65: Which option best describes a nonpoint-source pollutant affecting biodiversity?

Answer: Diffuse runoff from many locations (for example, farms and streets). Scattered sources make pollution harder to track and regulate.

Flashcard 66: Which variable in $S=cA^z$ represents habitat area, often reduced by humans?

Answer: $A$. Area is the key variable affected by habitat destruction.

Flashcard 67: What is inbreeding depression in conservation biology?

Answer: Reduced fitness from mating among relatives and harmful recessives. Related individuals share more harmful recessive alleles.

Flashcard 68: What is the Allee effect, and how can it raise extinction risk after habitat loss?

Answer: Low density reduces survival or reproduction; extinction risk increases. Very small populations struggle to find mates and reproduce.

Flashcard 69: What is carrying capacity $K$, and how can habitat degradation change $K$?

Answer: $K$ is max sustainable population; degradation lowers $K$. Reduced resources support fewer individuals in the population.

Flashcard 70: What is the typical biodiversity effect of pesticide use on insect communities?

Answer: Reduces non-target insects and alters food webs; diversity declines. Pesticides kill beneficial insects that support food webs.

Flashcard 71: What is a wildlife corridor, and what biodiversity problem does it address?

Answer: Habitat link between patches; reduces isolation and boosts gene flow. Connects isolated patches to allow movement and breeding.

Flashcard 72: What is an endemic species, and why is it vulnerable to habitat loss?

Answer: Species restricted to one area; limited range increases extinction risk. Cannot escape to other areas when local habitat is destroyed.

Flashcard 73: What is overfishing, and what is a common community-level consequence?

Answer: Excess fish harvest; food-web shifts and reduced diversity. Removes key species and disrupts predator-prey relationships.

Flashcard 74: What is an indicator species, and how is it used to infer biodiversity change?

Answer: Species sensitive to change; signals ecosystem health and diversity. Changes in these species reflect broader ecosystem condition.

Flashcard 75: What is genetic diversity, and why is it important for biodiversity under human change?

Answer: Variation in alleles; increases adaptability and resilience. More genetic variation provides better response to environmental changes.

Flashcard 76: What is eutrophication caused by fertilizer runoff?

Answer: Nutrient enrichment that triggers algal blooms and oxygen depletion. Excess nutrients fuel massive algae growth that consumes oxygen.

Flashcard 77: What is ecosystem resilience, and how does higher biodiversity affect it?

Answer: Ability to recover after disturbance; higher biodiversity increases it. More species provide more functional redundancy for recovery.

Flashcard 78: What is species evenness in a community biodiversity model?

Answer: How evenly individuals are distributed among species. Measures if species have similar or unequal abundances.

Flashcard 79: What is genetic drift, and why is it stronger in small human-isolated populations?

Answer: Random allele frequency change; stronger when population size is small. Random sampling effects are proportionally larger in small populations.

Flashcard 80: What is biodiversity, as used in ecology when modeling human impacts on ecosystems?

Answer: Variety of life at genetic, species, and ecosystem levels. Encompasses all levels from genes to entire ecosystems.

Flashcard 81: What is thermal pollution, and what is its typical effect on dissolved oxygen?

Answer: Warmer water from discharge; dissolved oxygen decreases. Warm water holds less dissolved oxygen than cool water.

Flashcard 82: What is the typical biodiversity effect of pesticide use on insect communities?

Answer: Reduces non-target insects and alters food webs; diversity declines. Pesticides kill beneficial insects that support food webs.

Flashcard 83: What is the greenhouse effect, and why does human-enhanced $CO_2$ matter for biodiversity?

Answer: Atmospheric heat trapping; added $CO_2$ drives warming and range shifts. Enhanced greenhouse effect accelerates climate change impacts.

Flashcard 84: What does the exponent $z$ represent in the species–area model $S=cA^z$?

Answer: How strongly richness increases with area (slope on log-log plot). Higher $z$ values mean richness drops faster with area loss.

Flashcard 85: What is a keystone species in biodiversity models?

Answer: Species with disproportionately large effects on community structure. Their loss causes cascading effects throughout the community.

Flashcard 86: What is an invasive species in models of human-caused biodiversity change?

Answer: Non-native species that spreads and harms native communities. Outcompetes natives and lacks natural predators or diseases.

Flashcard 87: What is bioindicator evidence that acid rain is reducing freshwater biodiversity?

Answer: Declines in sensitive species such as mayflies and some fish. Acid-sensitive species disappear first as pH decreases.

Flashcard 88: What is ocean acidification, and what organisms are especially impacted?

Answer: Lower ocean pH from $CO_2$; harms corals and shell-formers. Dissolved $CO_2$ makes seawater acidic, dissolving calcium structures.

Flashcard 89: What is the typical biodiversity effect of urbanization on native species?

Answer: Decreases native diversity; favors generalists and invasives. Urban environments favor adaptable species over specialists.

Flashcard 90: What is the Allee effect, and how can it raise extinction risk after habitat loss?

Answer: Low density reduces survival or reproduction; extinction risk increases. Very small populations struggle to find mates and reproduce.

Flashcard 91: What is eutrophication caused by fertilizer runoff?

Answer: Nutrient enrichment that triggers algal blooms and oxygen depletion. Excess nutrients fuel massive algae growth that consumes oxygen.

Flashcard 92: What is a keystone species in biodiversity models?

Answer: Species with disproportionately large effects on community structure. Their loss causes cascading effects throughout the community.

Flashcard 93: What is the typical biodiversity effect of establishing protected areas (reserves)?

Answer: Reduces habitat loss and overharvest; slows declines and extinctions. Protection removes major human threats to species survival.

Flashcard 94: Identify the main genetic risk when small populations become isolated by fragmentation.

Answer: Inbreeding and genetic drift reduce genetic diversity. Small isolated populations lose genetic variation through breeding patterns.

Flashcard 95: What is hypoxia, and how is it linked to eutrophication and biodiversity loss?

Answer: Low dissolved oxygen; causes die-offs and reduced species richness. Fish and other aquatic organisms cannot survive without adequate oxygen.

Flashcard 96: What is the primary biodiversity effect of converting forest to monoculture cropland?

Answer: Lower species richness and evenness due to habitat simplification. Monocultures eliminate habitat complexity and food sources.

Flashcard 97: What is ecosystem resilience, and how does higher biodiversity affect it?

Answer: Ability to recover after disturbance; higher biodiversity increases it. More species provide more functional redundancy for recovery.

Flashcard 98: What is a biodiversity hotspot, and why is it prioritized for conservation?

Answer: High endemism and high threat; protects many unique species. Conservation efforts here protect maximum species per unit effort.

Flashcard 99: What is hypoxia, and how is it linked to eutrophication and biodiversity loss?

Answer: Low dissolved oxygen; causes die-offs and reduced species richness. Fish and other aquatic organisms cannot survive without adequate oxygen.

Flashcard 100: What is a trophic cascade, often triggered by human removal of predators?

Answer: Food-web changes across trophic levels after predator loss. Effects ripple down from top predators to primary producers.