Ecology The scientific study of interactions between organisms and their environment
1. Biosphere = thin zone that contains ALL life of Earth
2. Ecosystem = a self supporting group of communities and their physical environment Biotic factors: all the LIVING organisms that inhabit an environment bio- = life Abiotic factors: all the NONLIVING part of the environment a- = without; a bio tic = without life
rock, flower, sun, popcorn, grass, soil, water, animal, tree, carcass Living (biotic) Nonliving (abiotic) Dead
Flower Grass Animal Tree Living (biotic) Nonliving (abiotic) Dead
Living (biotic) Nonliving (abiotic) Dead Flower Grass Animal Tree Rock Sun Soil Water
Living (biotic) Nonliving (abiotic) Dead Flower Grass Animal Tree Rock Sun Soil Water Popcorn Carcass
3. Community = all the living organisms in a specific area (Ex. Pond, forest)
4. Population: = all the individuals of the same species living in the same area at the same time 5. Organism = any living thing
Overview: (largest smallest) Biosphere Ecosystem Community Population Organism How to remember order? Big Elephants Consume Peanuts Often
Habitat = the place an organism lives Niche = the role (job) an organism has in it s community
Species = a group of like organisms that can reproduce AND have fertile offspring
Horse + Donkey = Mule A mule is not fertile. In order to make more mules, there must be more (horse + donkey)
Lion + tiger = liger Babies are sterile therefore NOT a species
Symbiosis = the relationship in which there is a close and permanent association between organisms of different species 3 types:
Relationship in which both organisms benefit Organism 1 = = Benefit Organism 2 = = Benefit
Ants and the acacia tree
= relationship in which one species benefits and the other is neither harmed nor benefited Organism 1 = = benefit Organism 2 = = no harm, no benefits
Spanish moss growing on trees
Relationship in which one species benefits and the other is harmed Organism 1 = = benefit Organism 2 = = harmed
Tapeworms
Relationship Organism 1 Organism 2 Mutualism Benefit Benefit Commensalism Benefit No benefit, not harmed Parasitism Benefit Harmed
1. Producers: Also called autotrophs auto- = self troph = feeding These are organisms that make their own food Ex. green plants
2. Consumers: Also called heterotrophs hetero- = different Organisms that can NOT make their own food Three categories: A. herbivores: eat plants (primary consumer)
B. carnivores: eat other consumers; eat meat (secondary/tertiary consumers) C. omnivores: eat both plants and animals (tertiary consumers)
3. Decomposers: break down organic matter and return it to the environment
The flow of energy and organic molecules from organism to organism Energy for this system originates from the SUN Food chains ALWAYS begin with a PRODUCER
Look at the image to the right and write the correct food chain Grass insects frog owl hawk
Food Webs Complex relationships formed by interconnecting and overlapping food chains
1. Pyramid of numbers The higher up the food chain the lower the number of organisms
2. Pyramid of energy 90% of the energy is lost to the environment at each level of the food chain 3. Pyramid of biomass The amount of biomass decreases at each level of the food chain
Limiting factor: any biotic or abiotic factor that restricts an organism s ability to survive Ex. Food supply, water supply, living space Tolerance: the ability to withstand fluctuations in biotic and abiotic environmental factors
SUCCESSION = the orderly, natural change in communities over time Primary succession: development of living communities from BARE ROCK NO soil present Ex. Rock lichens moss ferns shrubs trees mature trees
Pioneer organism: the first organism to inhabit a community (ex. lichens) Climax community: a stable, mature community that undergoes little or no succession Primary succession takes a relatively long time to reach this point
Secondary succession: the development of living communities that takes place when a community is disrupted by natural disasters or human impact Soil IS present Takes less time to reach climax community Ex. Abandoned farms, fires
Exponential growth: when the number of organisms increases by an ever-increasing rate. 2 4 8 16 32 64 128 256 etc J-shaped curve
Carrying capacity: the number of organisms of a population a particular environment can support over an indefinite period of time S-shaped curve
1. Birth rate 2. Death rate 3. Growth rate = birth rate death rate 4. Immigration: movement INTO an area 5. Emigration: movement OUT of an area