Ecology= the study of interactions among organisms and their environment.
Biosphere= the portion of earth that supports life.
Abiotic factors= non-living parts of the environment
Biotic factors= living parts of the environment
Levels of Organization in Ecology:
1. organism (one thing)
2. population (many things of the same species)
3. communities (a mix of different species)
4. ecosystem (living things and the environment)
5. biosphere (contains all ecosystems)
habitat= place where an organism lives
niche= the role and position a species has in its environment
symbiosis= "living together"; a relationship between two organisms
1. commensalism= one organism benefits, the other is
neither benefitted or harmed.
2. mutualism= both organisms benefit
3. parasitism= one organism benefits, the other is harmed
*energy flow= 10% is passed on, 90% is wasted
autotrophs= producers; make food; plants
heterotrophs= consumers; cannot make their own food
Three types of heterotrophs
1. herbivores= only eat autotrophs (plants)
2. carnivores= eat other heterotrophs (meat)
3. omnivores= eat both autotrophs and heterotrophs
scavengers= eat dead stuff; vultures, buzzards
*decomposer= break down the complex compounds of dead and decaying plants and animals into things that can be absorbed and used by organisms.
**arrow shows direction of ENERGY FLOW**
trophic level= each step in a food chain