AP Biology · Unit 8
Ecology
In short
Unit 8: Ecology in AP Biology covers 7 topics: Responses to the Environment, Energy Flow Through Ecosystems, Population Ecology, Effect of Density on Populations and 3 more. Open each one for what you need to know, a self-check list and how it is tested on the exam.
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What is in Unit 8: Ecology?
Unit 8: Ecology
8.1 Responses to the Environment
- I can describe how organisms communicate through various mechanisms and how signaling behaviors can result in differential reproductive success.
- I can explain how responses to information are vital to natural selection, and how innate, learned, and cooperative behaviors increase survival and reproductive success.
8.2 Energy Flow Through Ecosystems
- I can explain how organisms use energy to maintain homeostasis, including the differences between endotherms and ectotherms.
- I can describe how reproductive strategies change in response to energy availability.
- I can list the ecological levels of organization.
- I can describe the components of biogeochemical cycles, including abiotic and biotic reservoirs.
- I can describe the processes and reservoirs involved in the hydrologic cycle.
- I can explain the four main parts of the carbon cycle.
- I can describe the steps and microorganisms involved in the nitrogen cycle.
- I can explain how phosphorus cycles through the environment and living organisms.
- I can link changes in energy availability to changes in population size.
- I can describe how changes in energy resources or producer biomass affect trophic levels.
- I can distinguish between photosynthetic and chemosynthetic autotrophs.
- I can explain how heterotrophs capture energy by consuming organic matter.
8.3 Population Ecology
- I can describe how populations consist of individuals of the same species that interact with each other and their environment.
- I can explain how an organism's adaptations relate to how it obtains and uses energy and matter.
- I can explain how population growth dynamics depend on birth rate, death rate, and population size, and calculate population growth.
- I can describe how reproduction without constraints leads to exponential growth and calculate exponential growth rates.
8.4 Effect of Density on Populations
8.5 Community Ecology
- I understand that communities change over time based on the interactions between populations of different species.
- I can describe how competition, predation, and symbioses (parasitism, mutualism, commensalism) drive population dynamics.
8.6 Biodiversity
- I can describe the relationship between the diversity of an ecosystem and its resilience to environmental changes.
- I can explain why natural and artificial ecosystems with fewer components and less diversity are less resilient.
- I can identify the roles of keystone species, producers, and essential abiotic and biotic factors in maintaining ecosystem diversity.
- I can explain how adding or removing a component affects an ecosystem's short-term and long-term structure.
- I can describe the disproportionate impact of keystone species and predict the likelihood of ecosystem collapse if they are removed.
8.7 Disruptions in Ecosystems
- I can describe how an adaptation is a genetic variation favored by selection that provides an advantage in a particular environment.
- I can explain heterozygote advantage, where the heterozygous genotype has a higher relative fitness than homozygous genotypes.
- I can describe how the introduction of invasive species allows them to exploit new niches and outcompete native species.
- I can explain how human impacts like biomagnification and eutrophication drive changes in ecosystems and can cause extinctions.
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Ecology: common questions
What is in Unit 8: Ecology?
It covers 7 topics: 8.1 Responses to the Environment; 8.2 Energy Flow Through Ecosystems; 8.3 Population Ecology; 8.4 Effect of Density on Populations; 8.5 Community Ecology; 8.6 Biodiversity; 8.7 Disruptions in Ecosystems.
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