Topic 2 Flashcards
Organism
Single individual
Species
Group of organisms capable of exchanging genes
Population
A group of the same species, in the same place, at the same time, that can interbreed
Community
A group of several different species who live in the same place at the same time
Fundamental niche
The entire range of conditions in which a species could live
Realized niche
The actual conditions under which a species lives (usually due to competition)
Limiting factors
Sunlight, precipitation/water availability, salinity, soil nutrients, food
Producers
Make their own food using co2 & sunlight
Trophic level 1
Autotrophs
Consumers
Heterotrophs
Feed on other organisms to obtain energy
2nd trophic level
Green plants PP
1st level
Herbivores (PC)
2nd level
Function: to keep each other in check thru negative feedback and disperse seeds
Carnivores and omnivores
Secondary consumer or tertiary consumer.
3rd or 4th level
Function: to pollinate flowers and remove diseased animals from populations
What do pyramids of numbers show
The # of organisms at each trophic level in a food chain at a time
Pro: simple, good for comparing change
Con: organisms included regardless of size, numbers can be too great to express accuracy
Period of biomass
Mass of each individual at each trophic level
Pro: better than pyramid of numbers
Con: only uses samples, organisms must be killed for measurement, organisms w same biomass might have different energy content
What do pyramids of productivity show
The rate of the flow of energy or mass thru each trophic level
Pro: must accurate, good for comparison
Con: hard to collect data, hard to assign omnivores to trophic levels
Where does the majority of energy on earth come from?
Solar radiation
Where does the energy go
35% reflected back to space
Absorbed by plants and soil -> heats up water and soil
Only 1-4% is available for plants photosynthesis
Energy ___, matter ____
Energy flows, matter cycles
Primary productivity
Conversion of light energy to chemical energy within plant cells
Gross primary productivity (GPP)
Measuring a plants energy uptake by amount of sugar produced
Net primary productivity (NPP)
The rate at which plants accumulate dry mass
Difference between rate of photosynthesis and rate of respiration
NPP=GPP-R
Secondary productivity
Energy that is transferred from plants to consumers
Assimilated food energy
Absorbed by animals and used to power life processes
Gross secondary productivity (GSP)
Total energy assimilated (taken up) by consumers.
GSP= food eaten-fecal loss
