Biology
Ecology
the study of the interactions between organisms and their environment
ecosystem
group of organisms that react with their environment
population
all the members of a particular species living in an area
habitat
place where plant/animal lives
community
all the organisms living in one area
biotic factors + examples
living factors in an ecosystem:
- food
- competition
- human intervention
abiotic factors + examples
non-living factors of an ecosystem:
-light intensity
-soil PH
-temperature
Climatic factors
refer to weather over long period of time:
-temp
-rainfall
-wind
Edaphic factors
relate to the soil:
-soil PH
-water content
-type of soil
Aquatic factors
relate to organisms living in/near water:
-O2 conc
-light
The ____ is the primary source of energy for our planet
sun
Flora
plants in an ecosystem
Fauna
animals in an ecosystem
producers
organisms that make their own food through photosynthesis
__% of energy is passed onto other organisms
10%
consumers
take in food from other organisms
decomposers
feed on and brewk down dead organic matter e.g bacteria
detritus feeders
organisms that feed on small pieces of dead matter e.g worms
food chain
sequence of organisms showing transfer of energy from one organism to the next
trophic level
feeding position in a food chain
food web
consists of two or more interlinked food chains
ecological niche
functional role an organism plays in its community
pollution
any harmful addition to the environment
conservation
wise management of the environment
competition
organisms actively struggling for a resource that is in short supply
contest Vs scramble competition
contest competition: there's only one winner, survival of the fittest.
scramble competition: all organisms get some of the resource. e.g overcrowding of seedlings in flowerbed
adaptation
any alteration that improves an organisms chances of survival and reproduction.
2 types:
-behavioural
-structural
predator
organism that catches, kills and feeds on another organism (its prey)
parasitism
relationship between two different species that live in close associstion where one organism benefits by feeding on the other causing it harm
a parasite
organism that takes food from a live host and usually causes harm
ectoparasites
live on outside of host e.g ticks/fleas
endoparasites
live inside the host e.g tapeworms in human intestines
symbiosis
relationship between different species that live in close association where at least one of them benefits
mutualism
form of symbiosis in which both organisms benefit e.g nitrogen cycle
factors affecting human population
war
famine
contraception
disease