Biology Flashcards: Explain Limiting Factors On Population

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This deck focuses on Explain Limiting Factors On Population, giving you a quick way to review the definitions, rules, and examples that matter most for Biology.

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Flashcard 1: What is habitat loss as a limiting factor?

Answer: Reduced habitat lowers available resources and decreases carrying capacity. Reduces available space and resources needed for population maintenance.

Flashcard 2: What is carrying capacity ($K$)?

Answer: The maximum population size an environment can sustainably support. Determined by available resources and environmental conditions.

Flashcard 3: What is an abiotic limiting factor?

Answer: A nonliving factor (weather, climate, disasters) that limits population size. Physical environmental conditions that constrain population growth.

Flashcard 4: Which term describes factors like food, water, and shelter that organisms need to survive?

Answer: Limiting resources. Essential materials needed for survival, growth, and reproduction.

Flashcard 5: Which population growth model includes a carrying capacity ($K$)?

Answer: Logistic growth model. Growth slows as population approaches its environmental limit.

Flashcard 6: What is overharvesting as a limiting factor?

Answer: Human removal exceeds replacement, causing population decline. Unsustainable extraction rates lead to population collapse.

Flashcard 7: What is the effect of reduced habitat area on carrying capacity ($K$)?

Answer: It decreases $K$. Less space means fewer resources and lower maximum population.

Flashcard 8: What is density-dependent regulation of population size?

Answer: Population growth slows as density rises due to stronger limiting factors. Negative feedback prevents populations from exceeding carrying capacity.

Flashcard 9: What is resource limitation?

Answer: Population growth slows because essential resources become scarce. Competition intensifies as resources are divided among more individuals.

Flashcard 10: What is pollution as a limiting factor?

Answer: Contaminants reduce survival, fertility, or food quality. Toxins affect organisms regardless of population density.

Flashcard 11: What is limiting nutrient availability in aquatic ecosystems?

Answer: Shortage of key nutrients (often nitrogen or phosphorus) limits growth. Specific nutrients become the bottleneck for primary productivity.

Flashcard 12: What is the relationship between carrying capacity ($K$) and resource availability?

Answer: $K$ increases when resources increase and decreases when resources decrease. Resource abundance directly determines maximum sustainable population.

Flashcard 13: Which type of limiting factor affects populations regardless of their density?

Answer: Density-independent limiting factor. Its effect remains constant regardless of how many individuals are present.

Flashcard 14: Which limiting factor is best represented by competition for food?

Answer: Density-dependent limiting factor. Food scarcity becomes more intense as population density increases.

Flashcard 15: What is density-dependent regulation of population size?

Answer: Population growth slows as density rises due to stronger limiting factors. Negative feedback prevents populations from exceeding carrying capacity.

Flashcard 16: Which limiting factor is best represented by winter temperature extremes killing organisms?

Answer: Density-independent limiting factor. Abiotic factor that affects all individuals equally regardless of density.

Flashcard 17: What is a population dieback (crash) after overshoot?

Answer: A rapid population decrease due to depleted resources or stress. Population drops below $K$ due to resource depletion or stress.

Flashcard 18: Which population growth model includes a carrying capacity ($K$)?

Answer: Logistic growth model. Growth slows as population approaches its environmental limit.

Flashcard 19: Identify the limiting factor type: predation increases as prey density increases.

Answer: Density-dependent. Predation intensity increases with prey availability and density.

Flashcard 20: What is intraspecific competition?

Answer: Competition among individuals of the same species. Intensifies as population density increases due to resource overlap.

Flashcard 21: What is disease as a limiting factor?

Answer: Pathogens increase mortality or reduce reproduction, especially at high density. Spreads more rapidly in dense populations with frequent contact.

Flashcard 22: Identify the limiting factor type: a wildfire reduces a population in the same way at any density.

Answer: Density-independent. Fire kills organisms regardless of how many are present.

Flashcard 23: Identify the limiting factor category: temperature, rainfall, and floods.

Answer: Abiotic limiting factors. All represent physical environmental conditions affecting populations.

Flashcard 24: What is the role of water availability as a limiting factor?

Answer: Insufficient water reduces survival, growth, and reproduction. Essential resource required for all physiological processes.

Flashcard 25: What is the role of food availability as a limiting factor?

Answer: Low food supply reduces survival and reproduction. Primary resource that directly affects survival and reproductive success.

Flashcard 26: What is an abiotic limiting factor?

Answer: A nonliving factor (weather, climate, disasters) that limits population size. Physical environmental conditions that constrain population growth.

Flashcard 27: What is an invasive species as a limiting factor?

Answer: A nonnative species that reduces native populations via competition or predation. Disrupts ecosystem balance and reduces native species' carrying capacity.

Flashcard 28: What is parasitism as a limiting factor?

Answer: Parasites reduce host survival or reproduction, lowering population growth. Effect intensifies at higher host densities due to easier transmission.

Flashcard 29: Identify the limiting factor type: predation increases as prey density increases.

Answer: Density-dependent. Predation intensity increases with prey availability and density.

Flashcard 30: What is a biotic limiting factor?

Answer: A living factor (predators, competitors, parasites) that limits population size. Living organisms that interact with and affect population growth.

Flashcard 31: Identify the limiting factor type: a wildfire reduces a population in the same way at any density.

Answer: Density-independent. Fire kills organisms regardless of how many are present.

Flashcard 32: Identify the limiting factor category: competition, predation, and disease.

Answer: Biotic limiting factors. All involve living organisms interacting with the target population.

Flashcard 33: What is a limiting factor in population ecology?

Answer: An environmental factor that restricts population size or growth. Prevents unlimited population growth by constraining available resources or conditions.

Flashcard 34: Which type of limiting factor becomes stronger as population density increases?

Answer: Density-dependent limiting factor. Its effect intensifies as more individuals compete for limited resources.

Flashcard 35: What is resource limitation?

Answer: Population growth slows because essential resources become scarce. Competition intensifies as resources are divided among more individuals.

Flashcard 36: What is the primary effect of limiting factors on population growth rate?

Answer: They reduce birth rate, increase death rate, or both. Population size changes when births and deaths are affected.

Flashcard 37: Which factor is a classic density-dependent cause of population declines in crowded areas?

Answer: Disease transmission. Close contact in dense populations facilitates pathogen spread.

Flashcard 38: Which density-dependent factor is described by predators reducing prey numbers?

Answer: Predation. Creates predator-prey cycles that regulate both population sizes.

Flashcard 39: What is a population overshoot of carrying capacity ($K$)?

Answer: Population temporarily exceeds $K$, often followed by a decline. Resources become depleted when demand exceeds sustainable supply.

Flashcard 40: What is crowding stress as a limiting factor?

Answer: High density increases stress, reducing survival and reproduction. Physiological and behavioral responses to overcrowding reduce fitness.

Flashcard 41: What is an invasive species as a limiting factor?

Answer: A nonnative species that reduces native populations via competition or predation. Disrupts ecosystem balance and reduces native species' carrying capacity.

Flashcard 42: Identify the limiting factor type: a heat wave causes widespread mortality in a population.

Answer: Density-independent. Extreme temperatures affect all individuals regardless of population size.

Flashcard 43: Which density-dependent factor is described by predators reducing prey numbers?

Answer: Predation. Creates predator-prey cycles that regulate both population sizes.

Flashcard 44: Which limiting factor is most directly increased by higher population contact rates?

Answer: Disease spread. Close contact facilitates pathogen transmission between individuals.

Flashcard 45: What is interspecific competition?

Answer: Competition between individuals of different species. Can lead to competitive exclusion or resource partitioning.

Flashcard 46: Identify the limiting factor category: temperature, rainfall, and floods.

Answer: Abiotic limiting factors. All represent physical environmental conditions affecting populations.

Flashcard 47: What is crowding stress as a limiting factor?

Answer: High density increases stress, reducing survival and reproduction. Physiological and behavioral responses to overcrowding reduce fitness.

Flashcard 48: Which factor is a classic density-dependent cause of population declines in crowded areas?

Answer: Disease transmission. Close contact in dense populations facilitates pathogen spread.

Flashcard 49: Which limiting factor is best represented by competition for food?

Answer: Density-dependent limiting factor. Food scarcity becomes more intense as population density increases.

Flashcard 50: Identify the limiting factor type: a pesticide spill kills fish regardless of how many are present.

Answer: Density-independent. Chemical contamination affects organisms equally regardless of population size.

Flashcard 51: Which limiting factor is best represented by a hurricane affecting a population?

Answer: Density-independent limiting factor. Natural disasters affect populations equally regardless of density.

Flashcard 52: What is overharvesting as a limiting factor?

Answer: Human removal exceeds replacement, causing population decline. Unsustainable extraction rates lead to population collapse.

Flashcard 53: What is climate as a limiting factor?

Answer: Long-term temperature and precipitation patterns that restrict survival. Long-term conditions that determine species distribution and abundance.

Flashcard 54: Identify the limiting factor type: competition for nesting sites intensifies as density rises.

Answer: Density-dependent. Competition for limited resources becomes stronger with more competitors.

Flashcard 55: What is the main reason density-dependent factors are often stronger in crowded populations?

Answer: Higher contact rates increase competition, transmission, and encounter rates. Physical proximity increases interaction frequency and resource competition.

Flashcard 56: Identify the limiting factor type: a heat wave causes widespread mortality in a population.

Answer: Density-independent. Extreme temperatures affect all individuals regardless of population size.

Flashcard 57: What is the effect of increased predation pressure on prey population size?

Answer: It decreases prey population size by increasing mortality. Predators consume prey individuals, directly reducing population size.

Flashcard 58: What is the role of water availability as a limiting factor?

Answer: Insufficient water reduces survival, growth, and reproduction. Essential resource required for all physiological processes.

Flashcard 59: Identify the limiting factor type: a pesticide spill kills fish regardless of how many are present.

Answer: Density-independent. Chemical contamination affects organisms equally regardless of population size.

Flashcard 60: What is the difference between density-dependent and density-independent limiting factors?

Answer: Density-dependent varies with density; density-independent does not. Key distinction is whether the factor's strength changes with population size.

Flashcard 61: What is a limiting factor in population ecology?

Answer: An environmental factor that restricts population size or growth. Prevents unlimited population growth by constraining available resources or conditions.

Flashcard 62: Which population growth model assumes unlimited resources?

Answer: Exponential growth model. Population grows at constant rate without environmental constraints.

Flashcard 63: What is a density-independent population fluctuation?

Answer: Population changes driven by abiotic events, not by density. External environmental factors cause unpredictable population changes.

Flashcard 64: Which population growth model assumes unlimited resources?

Answer: Exponential growth model. Population grows at constant rate without environmental constraints.

Flashcard 65: What is the primary effect of limiting factors on population growth rate?

Answer: They reduce birth rate, increase death rate, or both. Population size changes when births and deaths are affected.

Flashcard 66: What is the effect of increased predation pressure on prey population size?

Answer: It decreases prey population size by increasing mortality. Predators consume prey individuals, directly reducing population size.

Flashcard 67: What is a population dieback (crash) after overshoot?

Answer: A rapid population decrease due to depleted resources or stress. Population drops below $K$ due to resource depletion or stress.

Flashcard 68: What is habitat loss as a limiting factor?

Answer: Reduced habitat lowers available resources and decreases carrying capacity. Reduces available space and resources needed for population maintenance.

Flashcard 69: Identify the limiting factor type: competition for nesting sites intensifies as density rises.

Answer: Density-dependent. Competition for limited resources becomes stronger with more competitors.

Flashcard 70: What is climate as a limiting factor?

Answer: Long-term temperature and precipitation patterns that restrict survival. Long-term conditions that determine species distribution and abundance.

Flashcard 71: Which limiting factor is best represented by a hurricane affecting a population?

Answer: Density-independent limiting factor. Natural disasters affect populations equally regardless of density.

Flashcard 72: Which type of limiting factor becomes stronger as population density increases?

Answer: Density-dependent limiting factor. Its effect intensifies as more individuals compete for limited resources.

Flashcard 73: Which limiting factor is most directly increased by higher population contact rates?

Answer: Disease spread. Close contact facilitates pathogen transmission between individuals.

Flashcard 74: What is a natural disaster as a limiting factor?

Answer: A sudden event (fire, flood, storm) that reduces population size. Unpredictable events that cause immediate population reductions.

Flashcard 75: Identify the limiting factor category: competition, predation, and disease.

Answer: Biotic limiting factors. All involve living organisms interacting with the target population.

Flashcard 76: Which term describes factors like food, water, and shelter that organisms need to survive?

Answer: Limiting resources. Essential materials needed for survival, growth, and reproduction.

Flashcard 77: What is limiting nutrient availability in aquatic ecosystems?

Answer: Shortage of key nutrients (often nitrogen or phosphorus) limits growth. Specific nutrients become the bottleneck for primary productivity.

Flashcard 78: Which type of limiting factor affects populations regardless of their density?

Answer: Density-independent limiting factor. Its effect remains constant regardless of how many individuals are present.

Flashcard 79: What is interspecific competition?

Answer: Competition between individuals of different species. Can lead to competitive exclusion or resource partitioning.

Flashcard 80: What is a density-independent population fluctuation?

Answer: Population changes driven by abiotic events, not by density. External environmental factors cause unpredictable population changes.

Flashcard 81: What is the effect of reduced habitat area on carrying capacity ($K$)?

Answer: It decreases $K$. Less space means fewer resources and lower maximum population.

Flashcard 82: What is territoriality as a limiting factor?

Answer: Limited territory reduces access to resources and breeding sites. Behavioral mechanism that maintains spacing and resource access.

Flashcard 83: Identify the limiting factor type: parasites spread more easily as hosts become more crowded.

Answer: Density-dependent. Transmission rates increase with host density and contact frequency.

Flashcard 84: Identify the limiting factor type: parasites spread more easily as hosts become more crowded.

Answer: Density-dependent. Transmission rates increase with host density and contact frequency.

Flashcard 85: What is eutrophication as it relates to limiting factors?

Answer: Excess nutrients cause algal blooms and oxygen loss, reducing populations. Nutrient excess creates oxygen depletion and toxic conditions.

Flashcard 86: What is the main reason density-dependent factors are often stronger in crowded populations?

Answer: Higher contact rates increase competition, transmission, and encounter rates. Physical proximity increases interaction frequency and resource competition.

Flashcard 87: What is the role of space or shelter availability as a limiting factor?

Answer: Limited habitat space reduces carrying capacity and breeding success. Physical environment determines maximum sustainable population size.

Flashcard 88: What is eutrophication as it relates to limiting factors?

Answer: Excess nutrients cause algal blooms and oxygen loss, reducing populations. Nutrient excess creates oxygen depletion and toxic conditions.

Flashcard 89: What is the relationship between carrying capacity ($K$) and resource availability?

Answer: $K$ increases when resources increase and decreases when resources decrease. Resource abundance directly determines maximum sustainable population.

Flashcard 90: What is parasitism as a limiting factor?

Answer: Parasites reduce host survival or reproduction, lowering population growth. Effect intensifies at higher host densities due to easier transmission.

Flashcard 91: What is the role of space or shelter availability as a limiting factor?

Answer: Limited habitat space reduces carrying capacity and breeding success. Physical environment determines maximum sustainable population size.

Flashcard 92: What is a biotic limiting factor?

Answer: A living factor (predators, competitors, parasites) that limits population size. Living organisms that interact with and affect population growth.

Flashcard 93: What is the role of food availability as a limiting factor?

Answer: Low food supply reduces survival and reproduction. Primary resource that directly affects survival and reproductive success.

Flashcard 94: Which limiting factor is best represented by a drought reducing plant growth?

Answer: Density-independent limiting factor. Water stress affects all organisms regardless of population size.

Flashcard 95: What is disease as a limiting factor?

Answer: Pathogens increase mortality or reduce reproduction, especially at high density. Spreads more rapidly in dense populations with frequent contact.

Flashcard 96: What is the difference between density-dependent and density-independent limiting factors?

Answer: Density-dependent varies with density; density-independent does not. Key distinction is whether the factor's strength changes with population size.

Flashcard 97: Which limiting factor is best represented by winter temperature extremes killing organisms?

Answer: Density-independent limiting factor. Abiotic factor that affects all individuals equally regardless of density.

Flashcard 98: What is a population overshoot of carrying capacity ($K$)?

Answer: Population temporarily exceeds $K$, often followed by a decline. Resources become depleted when demand exceeds sustainable supply.

Flashcard 99: What is territoriality as a limiting factor?

Answer: Limited territory reduces access to resources and breeding sites. Behavioral mechanism that maintains spacing and resource access.

Flashcard 100: What is intraspecific competition?

Answer: Competition among individuals of the same species. Intensifies as population density increases due to resource overlap.