AP Biology:: Ecology

What is a POPULATION, at the ecological level, and how does it differ from a COMMUNITY?

- **A)** A community refers only to a SINGLE species' individuals, while a population refers to MULTIPLE different species (the reverse of the actual definitions)
- **B)** A POPULATION is a group of INTERBREEDING individuals of the SAME species living in a given area, while a COMMUNITY is ALL the different species populations living and interacting together in that same area
- **C)** A population and a community refer to exactly the SAME concept, with no meaningful ecological distinction between them
- **D)** These terms have no actual relationship to how many species are being considered in a given area

What is an ECOSYSTEM, and how does it differ from a COMMUNITY?

- **A)** A community always includes MORE components than an ecosystem, rather than being a subset of it
- **B)** An ecosystem refers only to the abiotic environment, with NO living organisms included at all
- **C)** An ecosystem and a community refer to exactly the SAME concept, with no meaningful distinction regarding abiotic factors
- **D)** An ECOSYSTEM includes a COMMUNITY (all interacting species populations in an area) PLUS the surrounding ABIOTIC (non-living) environment, such as water, sunlight, temperature, and soil nutrients

What is EXPONENTIAL population growth, and under what general conditions does a population tend to grow exponentially?

- **A)** Exponential growth always produces a perfectly FLAT, unchanging population size over time
- **B)** Exponential growth refers to a population that DECREASES at an accelerating rate over time, rather than increasing
- **C)** This growth pattern has no actual relationship to resource availability within a population's environment
- **D)** A pattern of population growth where the population size increases at an ACCELERATING rate over time (producing a J-shaped growth curve), typically occurring when RESOURCES are essentially UNLIMITED and there are few constraints on growth

What is LOGISTIC population growth, and how does it differ from exponential growth?

- **A)** A pattern of population growth that starts off rapid but then SLOWS as the population approaches the environment's CARRYING CAPACITY (producing an S-shaped curve), reflecting REAL-WORLD limits on resources, unlike exponential growth's assumption of unlimited resources
- **B)** Logistic growth always produces the exact SAME J-shaped curve as exponential growth, with no meaningful distinction between the two patterns
- **C)** This growth pattern has no actual relationship to a population's carrying capacity or resource limitations
- **D)** Logistic growth means a population's growth rate continuously ACCELERATES indefinitely, never slowing down as resources become limited

What is CARRYING CAPACITY (often denoted 'K'), as it relates to logistic population growth?

- **A)** Carrying capacity is always identical for every species and every environment, regardless of the specific resources actually available
- **B)** Carrying capacity refers to the SMALLEST possible population size an environment can support, rather than the maximum
- **C)** This term has no actual relationship to the maximum population size an environment's resources can sustainably support
- **D)** The MAXIMUM population size that a particular environment can SUSTAINABLY support over the long term, given the available resources (food, water, space, etc.)

What is a DENSITY-DEPENDENT limiting factor on population growth (such as disease transmission or competition for food), and how does its effect change as population density changes?

- **A)** A density-dependent factor's effect on population growth remains exactly the SAME regardless of how crowded or sparse the population is
- **B)** A limiting factor whose effect on population growth becomes STRONGER as population DENSITY increases -- for example, disease spreads more easily and competition for limited resources intensifies when more individuals are crowded into the same area
- **C)** Density-dependent factors always have a WEAKER effect as population density increases, the reverse of the actual relationship
- **D)** This type of limiting factor has no actual relationship to a population's density or crowding level

What is a DENSITY-INDEPENDENT limiting factor on population growth (such as a wildfire, earthquake, or extreme weather event), and how does it differ from a density-DEPENDENT factor?

- **A)** A density-independent factor's effect always becomes STRONGER specifically as population density increases, identical to a density-dependent factor
- **B)** Density-independent factors only ever affect populations that have ALREADY reached their carrying capacity, never populations below it
- **C)** A limiting factor that affects a population's size REGARDLESS of how crowded or sparse the population currently is -- unlike a density-dependent factor, its impact does NOT intensify or weaken based on population density
- **D)** This type of limiting factor has no actual relationship to affecting a population's overall size

What is INTERSPECIFIC COMPETITION, as one type of species interaction within a community?

- **A)** Interspecific competition refers to competition occurring ONLY between individuals of the SAME species, with no actual involvement of different species
- **B)** This type of interaction has no actual relationship to competition for limited resources between different species
- **C)** Interspecific competition always BENEFITS both competing species equally, with no negative effect on either
- **D)** Competition for limited resources (like food, water, or space) between individuals of DIFFERENT species, which can negatively affect the population growth or survival of BOTH competing species