module 4 Flashcards
Ecology
the interactions of one organism with another as well as their environment
levels
Individual
Population
Community
Ecosystem
Biome
Biosphere
abiotic factors
nonliving features of an environment
Light
Wind
Temperature
Water
Availability
pH levels → soil and water
Salinity
Humidity
Minerals
biotic factors
living features of an environment
Predation
Competition (for resources)
Pathogens
Plants
Animals
Microbes
nitrogen cycle
→nitrogen fixing bacteria that is present in soil that fixes atmospheric nitrogen → soluble nitrogen compounds → when in the soil → decomposers (eg. bacteria and fungi) converts it to useful compounds taken up by plants → plants use nitrogen to make protein and nucleic acids
Carbon oxygen cycle
transfer of oxygen and carbon between living and non-living components of an ecosystem
Driven by photosynthesis (CO2 + H2O → (in presence of sunlight) C6H12O6) and cellular respiration (C6H12O6 + O2 → ATP + CO2 + H2O)
Competitive exclusion principle
Two species can’t coexist if they are competing for the same resource → one species will outcompete the other species and the second species is eliminated
Resource partitioning
species adapt to slight different niches so that they can coexist (different ecological niches but the same environment)
eg.red and yellow birds
food chains
- represent simple feeding relationships between organisms in an ecosystem
- Shows predation arrow goes from the organism which is being eaten to the organism that eats it
- represents the flow of energy
producer –> primary consumer –> secondary consumer –> tertiary consumer
food webs
- culmination of food chains from the same ecosystem
- organisms can exist on more than one trophic level
- allows us to see the relationship between different organisms in an ecosystem
- can show detritivores and decomposers
keystone species
- If it is reduced in numbers → potentially cause the ecosystem to collapse
- eg. cassowary –> spreads seeds across an ecosystem
trophic levels
broad divisions of the different levels throughout an ecosystem
- arranged into ecological pyramids
- pyramids of biomass
- pyramid of energy
- pyramid of numbers
pyramid of biomass
- loses about 10% of biomass as each trophic level goes higher
- compare matter
biomass
total dry weight of organisms in trophic level
pyramid of numbers
producer, herbivore, carnivore
pyramid of energy
represent energy of the entire trophic level
- energy is lost due to metabolic reactions
- lost due to kinetic energy and heat
how does extinction occur and mass extinction
ecological consequence –> loos f biodiversity –> loss of keystone species –> loss of ecosystems
- rate of extinction increases dramatically –> mass extinction due to human impacts (climate change, pathogens, introduced species and diseases, pollution)