All flashcards
Flashcard 1: 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 2: 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 3: 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 4: 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 5: Identify the limiting factor category: competition, predation, and disease.
Answer: Biotic limiting factors. All involve living organisms interacting with the target population.
Flashcard 6: 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 7: 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 8: 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 9: 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 10: 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 11: Identify the limiting factor category: temperature, rainfall, and floods.
Answer: Abiotic limiting factors. All represent physical environmental conditions affecting populations.
Flashcard 12: What is resource limitation?
Answer: Population growth slows because essential resources become scarce. Competition intensifies as resources are divided among more individuals.
Flashcard 13: What is intraspecific competition?
Answer: Competition among individuals of the same species. Intensifies as population density increases due to resource overlap.
Flashcard 14: 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 15: 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 16: 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 17: 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 18: 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 19: 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 20: Which population growth model assumes unlimited resources?
Answer: Exponential growth model. Population grows at constant rate without environmental constraints.
Flashcard 21: Which population growth model includes a carrying capacity (K)?
Answer: Logistic growth model. Growth slows as population approaches its environmental limit.
Flashcard 22: 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 23: 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 24: 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 25: 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 26: 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 27: Which limiting factor is most directly increased by higher population contact rates?
Answer: Disease spread. Close contact facilitates pathogen transmission between individuals.
Flashcard 28: 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 29: 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 30: 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.