AP Biology Unit 8 Ecology Vocab and Concepts

This is the AP Biology Unit 8 Ecology unit. Unit 8 is generally about 10-15% of the AP exam in May. You are expected to know that energy flows from the bottom of the energy pyramid to the top.

Define Population

organisms of the same species inhabiting the same area

what is the initial phase of a logistic curve?

lag phase

what is phase two of a logistic curve?

exponential growth phase

what is phase three of a logistic curve?

deceleration phase

what is the ‘final’ stage of a logistic curve?

met carrying capacity

what limits population growth? (provided by ecosystem)

carrying capacity

define density dependent limiting factors

population limitation because of sheer density

give examples of density dependent limiting factors

competition, the spread of disease, stress that lowers the birth rate, excess waste

define density independent limiting factors

limiting factors that do not rely on dense population

give examples of density independent limiting factors (3 things)

natural disasters, resources, pollutants

define carrying capacity

max amount of a population the ecosystem can support

what is a type I survivorship curve? (death rate, how many live to old age)

low death rate, many live to old age

what is a type II survivorship curve?

moderate death rate, die at all ages

what is a type III survivorship curve?

high death rate, die young few live to old age

what are characteristics of r-selected species?( environment, size, energy in offspring, number of babies, maturation speed, longevity, survivorship curve)

live in a unstable environment, small, put low energy into offspring, many babies, early maturation, short life, type III survivorship curve

what are characteristics of k-selected species?( environment, size, energy in offspring, number of babies, maturation speed, longevity, survivorship curve)

live in stable environment, large, put substantial energy in offspring, few babies, late maturity, long life, type I or II survivorship curve

what are invasive species effect on native populations?

they outcompete them

why do invasive species outcompete native species?

lack predators

define community

interacting populations in a common area

intraspecific interactions

interaction between the same species

interspecific interactions

interaction between different species

define biotic

living

define abiotic

non-living

define symbiosis

interaction between two organisms in close physical assosiation

define herbivory

animal eats plants

define predation

animal eats animal

define parasitism

an organism living in or on another animal

define mutualism

both species benefit from the interaction

define commensualism

an organism is unaffected while the other benefits

define ecological niche

role and position of species in an ecosystem

define realized niche

the exploited resources

define fundamental niche

potential resource exploitation

define competitive exclusion principle

no two species can occupy the same niche

define resource(niche) partitioning

natural selection drives competing species into different resource exploitation

define predator-prey coevolution

predator and prey evolve to outcompete eachother

define trophic cascade

removal or addition of top predator that drastically changes the lower levels

define keystone species

organism that defines an entire ecosystem

define species diversity

number and abundance of species in a certain area

define ecosystem

abiotic and biotic components interacting with each other

define primary producer(autotroph)

makes food for themselves, self feeder

define consumer(heterotroph)

eats food

define decomposer

breaks down leaf litter and non-living matter into simple substances

define photosynthetic producers

autotrophs that use sun to make their food (carbohydrates)

define chemosynthetic producers

autotrophs that use chemical substances from abiotic matter to make their food(carbohydrates)

define endotherms

their body temperature remains constant, generally mammals and birds, they make heat internally

define ectotherms

their body temperature is dependent on the environment, generally reptiles, they absorb heat from the enviorment

what is a trend between organism size and metabolism?

The bigger the organism the lower its metabolism

why do larger organisms have lower metabolism?

the bigger the organism the more it retains heat and does not have to produce more of it by converting food to heat as often as smaller organisms

define trophic levels

an organism’s position in the food chain

define 10% rule

only 10% of energy from the previous trophic level is transferred to the next

define food chain

linear flow of energy

define food web

multiple flows of energy from bottom to top (includes omnivores)

what is the effect of invasive species on ecosytems?

decrease biodiversity by eliminating native populations, and they alter habitats

define primary production

photosynthesis and chemosynthesis which is carbon fixation (synthesis of organic carbon through carbon dioxide)

define gross primary production

total number of carbon fixated through photosynthesis in a period of time

define net primary production

rate of accumulation of energy(carbohydrates), or rate of carbon fixation

define biomass pyramids

pyramid of trophic levels determined by the mass of the population

define energy pyramid

has to be a triangle with bigger base and smaller top, less energy is towards the top

define ecological effiency

90% of energy is lost through heat, and from discarded non digestible parts of the organism

define carbon fixation

process of converting inorganic carbon(CO₂) into organic building blocks used by plants