Unit 2- Principles of Ecology Flashcards
population density
total number of individuals living in a specific area
immigration
organisms that move into a population
emigration
organisms that move out of a population
mortality
death rate
natality
birth rate
exponential growth
amount of time it takes for population to double in size
R- selected species
many babies for survival, little parent care (insects, plants)
K - selected species
few babies, parental care (humans, large animals)
Biotic potential
the rate which a population could grow if nothing was holding it back (no limits)
carrying capacity
maximum number of individuals of a population that a environment can sustain (has limits)
density dependent control
factors that come into effect with population size (populations grow to capacity but are also dependent on outside factors)
ecology
scientific study of interactions among organisms and their environments
biosphere
portion of earth that supports life
abiotic
non-living parts (air, water, soil)
biotic
living parts (people, plants, animals)
levels of organization in ecology
1) Organism
2) population
3) community
4) ecosystems
5) biosphere
organism
an individual
population
group of organisms of one species in the same place
community
groups of populations that interact
ecosystems
communities & surrounding abiotic things (terrestrial-land, aquatic-bodies of water)
biosphere
all ecosystems
habitat
living place of organisms
niche
role “job” species plays in it’s environment (food, shelter, survival, reproduction)
symbiosis
living together
commensalism
one benefits, one gets nothing (ex: elephant & birds walking) q
multulism
both things benefit (ex: alligator & bird teeth cleaning)
parasitism
one lives off the other, but doesn’t kill it (ex: tick on a dog)
competition
between two or more species for a resource (food, other mates, ect.)
predator
animal or organism that hunts & kills prey for food
autotrophs
use energy from the sun or chemical component to make food
producers
organisms that make food in a community
types of consumers
- heterotrophs
- scavengers
- decomposers
heterotrophs
can not make food, must feed on other organisms
scavengers
eat on animals that have already died
decomposers
break down and absorb nutrients from dead organisms (recyclers)
primary consumer
animals that eat only plants
secondary consumer
animals that eat other animals
carnivore
only eats animals
herbivore
only eats plants
omnivore
eats both animals and plants
food chains
simple model to show how matter and energy move through an ecosystem
example of a food chain
plant –> insect –> frog –> snake
trophic levels
each organism in a food chain represents a feeding step in the passage of energy
5 trophic levels
- producers
- primary consumers (herbivores)
- secondary consumer (omnivores/carnivores)
4 & 5. top (carnivores
ecological pyramids
diagram that shows the relative amounts of energy in different trophic levels
food webs
model that shows all possible feeding relationships at each trophic level in a community
water cycle
- precipitation (rain, snow)
- evaporation (liquid to gaseous water)
- transpiration (evaporation from plants)
- condensation (gaseous water to liquid)
carbon cycle
- photosynthesis (how carbon gets from abiotic to biotic)
- respiration (how carbon gets from biotic to abiotic) (reverse of photosynthesis)
nitrogen cycle
(getting nitrogen into the soil)
1. lightning strikes
2. bacteria (through plants)
3. man-made (spraying fields with nitrogen) (rotating growing crops, ex: corn takes nitrogen out, beans bring nitrogen back)
phosphorus cycle
- short term (organisms dying)
- long term (rocks slowly decaying)
