AP Environmental

ecology

branch of biology studying relations between organisms and their environment

Species

group of similar organisms who freely interbreed with one another in the wild

population

group of organisms of the same species in the same place at the same time

community

natural association between all the populations of different species that live in the same area at the same time

atmosphere

layer of gas surrounding the Earth, traps heat from the sun, excess emissions cause more heat to be trapped

hydrosphere

Earth’s supply of water in all forms

lithosphere

the soil and rock of the earth’s crust

chemical energy

energy stored in bonds of molecules

radiant energy

energy transmitted as electromagnetic waves (radio, light, etc.)

thermal energy

energy from heat going from higher to lower temperature

first law of thermodynamics

energy cannot be created nor destroyed, the total energy content of an organism and it’s surroundings with be the same

second law of thermodynamics

when energy is converted from one form to another, some of it is degraded into heat, a less usable form that disperses into the environment

entropy

measure of disorder or randomness in the universe, usable energy has low , heat has high ___, increases over time.

photosynthesis

biological process in which light energy from the sun is captured and transformed into chemical energy of sugar molecules

cellular respiration

biological process in which molecules such as glucose and water are broken down into CO2 and water.

trophic level

organism’s position in the food chain, as the position gets higher they lose more energy

gross primary productivity

measure how much photosynthetic energy captured in a period of time

net primary productivity

total amount of plant biomass after cellular respiration has occurred in plant tissues

autotrophs

converts sunlight into energy via photosynthesis, aka producers

heterotrophs

consumers, acquire energy by by consuming other organisms

pyramid of energy

shows energy content of each trophic level, only 10% is passed on

pyramid of biomass

total amount of living material in an ecosystem at a given time, follows 10% rule

pyramid of numbers

census count of organisms per level

biotic

living parts of an ecosystem, such as plants and animals

abiotic

nonliving parts of an ecosystem, such as soil and water

food chain

sequence of organisms consuming other organisms

food web

network of multiple food chains

resource partitioning

members of the same species adapt differently to conserve scarce resources

fundamental niche

potential, idealized niche of an organism without competition

realized niche

the life and habitat an organism has due to competition

competitive exclusion

one species excludes another from a resource

density dependent factors

factors whose effect increases as population density increases

primary ecological succession

gradual establishment of a complex community in an area with only exposed rock

mutalism

both organisms benefit

parastitism

one organism benefits, the other is harmed

commensalism

one organism benefits, the other is unaffected

r-selected

species that have large amounts of offspring with no parental care

K-selected

few offspring, lots of parental care

primary ecological succession

gradual establishment of a community in an area with no previous life, soil, or sediment

secondary ecological succession

community establishing where a community already was