Unit 8 Active Recall Questions AP Bio (fully CED aligned)

Organisms respond to changes in the environment with what mechanisms? What do they mean?

Organisms respond through behavioral mechanisms, which are changes in actions or activity, and physiological mechanisms, which are changes in internal body processes.

In what environments can organisms respond to changes?

Organisms can respond to changes in both the internal environment and the external environment.

Do organisms exchange information, and what is the outcome?

Yes, organisms exchange information with one another in response to internal changes and external cues, and this exchange can change behavior, which changes reproductive success

How do organisms communicate with each other?

Organisms communicate through visual, audible, tactile, electrical, and chemical signals.

What do animals use signals for?

Animals use signals to indicate dominance, find food, establish territory, and ensure reproductive success.

What do innate and learned behaviors increase, and what are innate behaviors?

Innate and learned behaviors increase survival and reproductive success, and innate behaviors are inherited behaviors.

What is cooperative behavior?

Cooperative behavior is when organisms work together in ways that improve survival or reproduction.

What do organisms use energy for?

Organisms use energy to organize, grow, reproduce, and maintain homeostasis.

What are endotherms, and how do they get their energy?

Endotherms use thermal energy generated by metabolism to maintain a stable internal body temperature.

What are ectotherms, and how do they get their energy?

Ectotherms lack efficient internal temperature regulation and often regulate temperature behaviorally, such as by moving into sun or shade.

What does a net gain in energy lead to vs a net loss in energy?

A net gain in energy leads to energy storage, growth, and increased reproductive output, while a net loss of energy leads to loss of mass, reduced reproduction, and eventually death.

What is a reproductive strategy that could be used to conserve energy?

Some organisms alternate between asexual and sexual reproduction depending on energy availability.

What are the ecological levels of organization?

Ecological levels of organization include populations, communities, ecosystems, and biomes.

Energy does what through the environment while matter and nutrients do what between organisms and the environment?

Energy flows through ecosystems, while matter and nutrients cycle between organisms and the environment.

What are abiotic reservoirs?

Abiotic reservoirs are nonliving storage places in biogeochemical cycles.

What are biotic reservoirs?

Biotic reservoirs are living storage places in biogeochemical cycles.

In the water cycle, what are the major processes and what do they do?

The major processes are evaporation, which moves water into the atmosphere; condensation, which forms water droplets; precipitation, which returns water to Earth; and transpiration, which releases water vapor from plants.

In the carbon cycle, what are the major processes and what do they do?

Photosynthesis moves carbon from CO2 into organic molecules, cellular respiration returns carbon to CO2, decomposition breaks down dead matter and returns carbon, and combustion releases carbon as CO2.

What is the largest nitrogen reservoir?

The atmosphere is the largest nitrogen reservoir.

What performs the steps of the nitrogen cycle?

Microorganisms in the soil perform the major steps of the nitrogen cycle.

Tell the major processes of the nitrogen cycle and what they do

Nitrogen fixation converts N2 into ammonia or ammonium, assimilation is when organisms take in usable nitrogen, ammonification returns nitrogen to ammonium through decomposition, nitrification converts ammonium into other usable nitrogen forms, and denitrification returns nitrogen to the atmosphere as N2.

Tell how the phosphorus cycle operates

In the phosphorus cycle, weathering of rocks releases phosphate into soil and groundwater, producers take in phosphate, consumers obtain it by eating producers, and phosphorus returns to the environment through decomposition and excretion.

What are the trophic levels?

Trophic levels include producers, primary consumers, secondary consumers, tertiary consumers, quaternary consumers, and decomposers.

What can biomass or number of producers impact?

The biomass or number of producers can affect the number and size of higher trophic levels.

What are autotrophs?

Autotrophs are organisms that capture energy from physical or chemical sources in the environment.

What are photosynthetic organisms, and what is primary productivity?

Photosynthetic organisms capture energy from sunlight, and primary productivity is the rate at which photosynthetic and chemosynthetic autotrophs convert energy into organic substances.

What are chemosynthetic organisms?

Chemosynthetic organisms capture energy from small inorganic molecules and can do so in the absence of oxygen.

What are heterotrophs?

Heterotrophs are organisms such as carnivores, herbivores, omnivores, decomposers, and scavengers that obtain energy from organic matter.

How do heterotrophs obtain energy?

Heterotrophs obtain energy by consuming organic matter derived from autotrophs and incorporating that matter into their own tissues.

What is a population?

A population is a group of individual organisms of the same species that interact with one another and with the environment.

What is the population growth equation?

The basic population growth equation describes population change based on births, deaths, immigration, and emigration.

If reproduction occurs without constraints, what type of growth occurs?

If reproduction occurs without constraints, exponential growth occurs.

What is the exponential growth equation? Define each variable.

The exponential growth equation models population increase when resources are unlimited; N is population size, r is the per capita rate of increase, and time determines how population size changes.

In exponential growth, the larger the population size the increase or decrease in size over time?

In exponential growth, the larger the population size, the greater the increase in size over time.

What does population ecology focus on?

Population ecology focuses on how population size changes in response to births, deaths, and environmental conditions.

What is population density?

Population density is how many individuals of a population occupy a given area or volume.

What is carrying capacity?

Carrying capacity is the sustainable abundance of a species that can be supported by the ecosystem’s total available resources.

What are density-dependent factors?

Density-dependent factors are limiting factors whose effects become stronger as population density increases.

What are density-independent factors?

Density-independent factors are limiting factors that affect populations regardless of density.

What is the logistic growth equation? Define the variables.

The logistic growth equation models population growth when resource limits are considered; N is population size, r is the per capita growth rate, and K is carrying capacity.

When does population growth slow down?

Population growth slows down as population size approaches carrying capacity because available resources become more limiting.

Which is more realistic: logistic growth or exponential growth?

Logistic growth is more realistic than exponential growth because real populations are usually constrained by resource availability.

What is a community?

A community consists of interacting populations of different species living in the same area.

Tell Simpson’s Diversity Index and the variables

Simpson’s Diversity Index is a measure of community diversity based on the number of individuals in each species and the total number of individuals in the community.

What is a trophic cascade?

A trophic cascade occurs when changes at one trophic level cause effects that ripple through other trophic levels.

What is a niche?

A niche is the role of a species in its environment.

What is niche partitioning and its purpose?

Niche partitioning occurs when species divide resource use in different ways, reducing direct competition.

What is symbiosis?

Symbiosis is a close interaction between species.

What is parasitism?

Parasitism is a symbiotic relationship in which one species benefits and the other is harmed.

What is mutualism?

Mutualism is a symbiotic relationship in which both species benefit.

What is commensalism?

Commensalism is a symbiotic relationship in which one species benefits and the other is not significantly affected.

What is biodiversity?

Biodiversity is the variety of living components in an ecosystem.

What is resilience?

Resilience is the ability of an ecosystem to withstand or recover from environmental change.

Which ecosystems are less resilient to environmental changes?

Natural and artificial ecosystems with fewer component parts and little diversity are often less resilient to environmental changes.

What factors help maintain ecosystem diversity?

Keystone species, producers, and essential abiotic and biotic factors help maintain ecosystem diversity.

What happens when keystone species are removed?

When a keystone species is removed, the ecosystem often collapses or changes drastically.

The addition or removal of any ecosystem component can affect the ecosystem’s what kind of structure?

The addition or removal of any ecosystem component can affect the ecosystem’s short-term and long-term structure.

What is an adaptation?

An adaptation is a genetic variation favored by natural selection that appears as a trait providing an advantage in a particular environment.

What is heterozygote advantage?

Heterozygote advantage occurs when the heterozygous genotype has higher relative fitness than either homozygous genotype.

What is an invasive species and what is the harm?

An invasive species is a species introduced into a new ecosystem where it may exploit a niche free of predators or competitors or outcompete native species for resources, harming the ecosystem.

What is biomagnification?

Biomagnification is the increasing concentration of harmful substances at higher trophic levels.

What is eutrophication?

Eutrophication is nutrient enrichment of water that causes ecosystem disruption, often through algal blooms and oxygen loss.

What are biogeographical studies and what do they help illustrate?

Biogeographical studies examine the distribution of organisms and ecosystems across space and time and help illustrate how ecosystem distribution changes over time.

What other events affect habitat change and ecosystem distribution?

Geological and meteorological events affect habitat change and ecosystem distribution.