ap bio unit 8: ecology

ecology

deals with organisms and their relationships to other organisms and the environment

population

certain group of one species that lives in the same place

community

group of several species that live in the same place

ecosystem

community + abiotic factors

autotroph

organism that makes energy from physical or chemical sources in the environment (e.g. plant)

heterotroph

makes energy from carbs, lipids, etc. (e.g. human)

trophic levels

producer → primary consumer → secondary →tertiary → quaternary

primary consumer

herbivore

secondary consumer

omnivores/carnivores

tertiary consumer

elite predators

dynamic stability hypothesis

fluctuations are higher up in the food chain, so top predators are more susceptible to extinction. food webs are shorter in unstable envs.

endotherm (warm blood)

regulate temperature by changing internal processes (e.g. shivering), less adaptable to temp changes

ectotherm (cold blood)

body temp is based on environment, so they are more adaptable to diff envs (they don’t need to use as much oxygen to regulate temp)

density dependent limiting factors

competition, disease, etc.

density inpendent limiting factors

nuke

intraspecific competition

bear vs bear

interspecific competition

bear vs. lion

mutualism

both species benefit

commensialism

one benefits, one is not harmed

predatory

one eats another

parasitism

one benefits, one is not harmed

competitive exclusion principle

two specifies that require the same resource cannot live indefinitely in same habitat

ecological niche

sum of all biotic + abiotic factors a species uses (allows for species to coexist)

realized niche

niche actually occupied as a result of limiting factors (e.g. someone else occupying part of the niche)

fundamental niche

a set of conditions in which an organism can live in the absence of competitors (greater than realized)

niche partitioning

decrease in competition between two similar species over limited resources since each is accessing them differently (some bird types may stay high in trees while others are low)

character displacement

evolutionary change that happens when two species have the same env. (favors a divergence in traits to occupy their own niches)

species richness

number of unique species in a community

diversity

a measure of richness + abundance of indivs. within each species

simpsons diversity index

the higher the value, the more diversity (based on number of total organisms related to the number in each species) → favors more even numbers

primary productivity

rate at which autotrophs produce biomass from inorganic sources

gross primary productivity

amt of carbon fixed into glucose during photosynthesis (measured by total oxygen production)

net primary productivity

(NPP + R = GPP) subtract rate of respiration from gross o2 prod

algal bloom

fertilizer dumped into river, other plants don’t get sunlight so they die (no o2), bacteria decomposers use up even more o2 and everything goes bad

zoo and phytoplankton

zooplankton are primary consumers that eat the autotroph phytoplankton