ecology Flashcards
phrase to remember levels of organization
“Big Elephants Can Party Hard Nightly”
ecology
how biotic (living) things interact with other biotic + abiotic factors - all things in an ecosystem are linked to each other.
biosphere
part of the earth where all life exists, not all life is equally distributed in biosphere.
ex. earth
ecosystem
all living (biotic) + non-living (abiotic) parts in a specific area.
ex. pond: ducks, fish, soil, rocks
community
all biotic factors of an ecosystem. form a system of production, consumption, and decomposition.
ex. fish, frogs, turtles, algae, bacteria
population
all members of the same species in an ecosystem that live in the same area and share resources.
ex. small-mouth bass in a pond
habitat
surroundings/environment of a particular organism (home).
ex. dam of a pond
niche
an organism’s job/role.
ex. consume small fish for population to stay under control
autotroph:
organism that makes its own food from solar energy.
heterotroph
consumers that feed off of autotrophs or other heterotrophs for energy.
trophic levels
levels of feeding in an ecosystem
producer
autotroph, makes its own food.
primary consumer
eats autotroph/producer
secondary consumer
eats primary consumer: herbivore
tertiary consumer
eats secondary consumer: omnivore, carnivore, scavenger
how much energy passes to next trophic level?
10%, 90% is used by organism as it tries to escape, etc.
level of energy gets lower and lower up the trophic levels – that is why we can’t have too many tiers.
decomposers
bacteria + fungi that break down dead plants and animal tissue + return nutrients back into soil.
examples of energy transfer
food chain, food web, energy pyramid
food chain
sequence of one organism feeding upon another at a lower trophic level.
food web
web of interconnected food chains; more complex than food chains.
predator v. prey relationship
important to control population numbers
symbiotic relationship
living together, benefits at least one organism
mutualism
both organisms benefit (+,+)
ex. bee + flower
commensalism
one organism benefits, other isn’t benefited or harmed (+,0)
ex. remora fish + shark
parasitism
one organism benefits, other is harmed (+, -)
ex. ticks on dogs
host
organism affected by symbiote
symbiote
lives in or on the host
acid rain
Sulfur or nitrogen containing compounds are released by combustion (burning fossil fuels), mix w/ H2O and create acid rain. Rain water is very acidic (pH 3), decays plants, aquatic animals die, damages soil, and kills enzymes needed for growth.
H2O + Co2 -> H2So3
ozone depletion
When chlorofluorocarbons (CFC’s) react w/ ozone in the stratosphere. Break down ozone by pulling an oxygen away. Ozone protects earth from the sun’s harmful UV rays (skin cancer + cataract causing). O3.
global warming/climate change
Intensified greenhouse effect. Greenhouse effect traps heat in earth’s atmosphere, and CO2 creates more particles that traps heat in atmosphere. CO2, methane, and nitrous oxide. Rises global temperatures, melts ice caps, etc.
Biomagnification
/bioaccumulation
Substance moves through the food chain and increases in quantity throughout trophic level. Might result in disease and death for organisms that accumulate too much.
Population growth/habitat destruction
Population starts -> grows a lot -> meets carrying capacity. Based on resources, limiting factors, carrying capacity could change in respect to the environment.
Humans: excessive human growth, needing more resources, get more resources by clearing forests.
Non-native or invasive species
Species brought to an area that it is not indigenous to: no natural predators, no limiting factors, population grows exponentially and harms existing populations.
Eutrophication
Excess nitrogen in water, algal bloom that covers the water and blocks the light so plants at the bottom have no food. Bacteria and decomposers feed on dead producers and multiply in excess. Excess bacteria will do cellular respiration until water becomes anoxic (no oxygen), everything dies because it cannot do cellular respiration.
how can humans stop acid rain?
Burn less fossil fuel, research more about alternative energy (wind, solar, etc.)
how can humans stop ozone depletion?
Ban CFCs, Montreal protocol 1989 agreed to phase CFCs out.
how can humans stop global warming?
Drive less, unplug appliances, conserve electricity @ home.
how can humans stop biomagnification?
Banned use of DDT, stopped using fat soluble pesticides -> stops moving up the trophic levels.
how can humans stop population growth/habitat destruction?
Make responsible choices about family planning.
how can humans stop invasive species?
Don’t bring or transport food or organisms into the country.
how can humans stop eutrophication?
Don’t use excessive fertilizers, stop sewage run off, stop burning fossil fuels.
Why is the Nitrogen Cycle needed?
Air is 78% nitrogen, but not in a usable form for plants, the nitrogen cycle “fixes” the nitrogen into its usable form.
Nitrogen Fixation
bacteria in the roots of legumes change nitrogen/N2 into usable form to build proteins.
Ammonification + Nitrification
bacteria change N2 into usable nitrogen/NO3 or NO2– so plants can make protein.
Assimilation
plants will absorb/take in usable form (NO3- or NO2-) into their roots + use it to build plant proteins.
Decomposition
heterotrophic decomposers/bacteria + fungi return nitrogen back into soil.
Denitrification
Nitrates (NO3-) returned to the atmosphere as N2 by bacteria.
photosynthesis equation
6CO2 + 6H2O + light -> C6H12O6 + 6O2
cellular respiration (aerobic)
C6H12O6 + 6O2 -> 6CO2 + 6H2O + 34-38 ATp
CO2 levels
photosynthesis (⬇)
cellular respiration (⬆) decomposition (⬆)
combustion (⬆)
deforestation (⬆)
linear growth
growth in a straight line, populations DO NOT grow this way
Logistic or S-Shaped Growth Curve
most populations grow this way
Lag phase
just getting started, organisms are reproducing
Exponential growth
numbers of organisms are increasing rapidly because of good environmental conditions, enough food, shelter, and few predators.
Carrying capacity
(K) maximum number of organisms the environment can support. Two types of limiting factors.
density dependent limiting factors
density-dependent (too many organisms, food, shelter, disease)
density independent limiting factors
density-independent (limit regardless of number of organisms, natural disasters, weather, temperature)
Stabilization phase
Stabilization phase
other factors
predation (prey relationships good for health of natural populations, usually the young, weak, or diseased members are caught by predators), competition, and crowding/stress
