Effect of Density on Populations - AP Biology
- What happens to mortality rates as density increases?
- Mortality rates often increase. Stress, disease, and competition increase death rates.
- State one consequence of low population density.
- Reduced genetic diversity. Small populations may lack genetic variability for adaptation.
- Identify a consequence of resource depletion in dense populations.
- Increased competition. Depleted resources intensify struggle among remaining individuals.
- What does the phrase 'density-dependent regulation' refer to?
- Population regulation by factors influenced by density. Negative feedback mechanisms control population size automatically.
- What is the relationship between population density and resource availability?
- Inverse relationship; high density reduces resources. As density increases, available resources per individual decrease.
- What effect does low density have on mating success?
- Reduced mating opportunities. Few individuals make finding mates more difficult.
- Which factor can cause a population crash?
- Exceeding carrying capacity. Resources become insufficient to support large populations.
- How can high population density lead to evolutionary changes?
- Selective pressure increases. Competition favors traits that improve survival success.
- How do populations achieve equilibrium at carrying capacity?
- Birth and death rates balance. Population stabilizes when births equal deaths.
- What is an example of a human-induced density-independent factor?
- Pollution. Chemical contamination affects populations regardless of density.
- What effect does high population density have on competition?
- Increases competition for resources. More individuals compete for limited resources available.
- What is population density?
- Number of individuals per unit area or volume. Standard measurement expressing how crowded organisms are in their habitat.
- How does crowding affect reproductive rates?
- Crowding can lower reproductive rates. Space limitations and stress reduce breeding success.
- Identify a density-dependent factor example.
- Competition for resources. Intensifies as population density increases, limiting growth.
- What is a potential result of exceeding the carrying capacity?
- Population decline. Population crashes when resources cannot support numbers.
- How does human activity typically affect carrying capacity?
- Often increases carrying capacity temporarily. Technology and agriculture increase resource availability.
- What is logistic growth?
- Population growth that slows as it reaches carrying capacity. S-shaped curve shows growth slowing near capacity limits.
- What is exponential growth?
- Population growth at a constant, rapid rate. J-shaped curve shows unrestricted growth without limits.
- How does intraspecific competition affect population density?
- Regulates population size. Competition within species controls population size naturally.
- What is the effect of low population density on disease spread?
- Decreases the spread of disease. Fewer contacts between individuals reduce disease transmission.
- Identify a density-independent factor example.
- Natural disasters. Affect populations regardless of their density levels.
- How does population density affect immigration?
- Higher density can reduce immigration. Crowded areas are less attractive to new immigrants.
- What role do density-independent factors play in population dynamics?
- Cause fluctuations independent of density. These factors create unpredictable population changes.
- How does high density affect organismal stress levels?
- Increases stress levels. Crowding triggers physiological stress responses in organisms.
- What is the effect of density on territorial behavior?
- Increases intraspecific aggression. Crowding increases fights over limited territory space.
- How do changes in density affect species interactions?
- Can alter predator-prey dynamics. Density changes affect competition and predation rates.