Energy Flow and Food Webs Flashcards
POP’s
Persistent organic pollutants
Endocrine disruptors
hormone mimics
How are ecological roles of organisms determined?
by their trophic level
What does energy transfer from one trophic level to the next depend on?
food quality and consumer abundance and physiology
what does a trophic pyramid portray?
relative amounts of energy biomass in each trophic level
What gets dispersed in the transfer from one trophic level to the next
Energy
What factors do you think determine how much energy flows from one trophic level to the next?
Amount of NPP
Proportion of each trophic level consumed by the one above it
Nutritional content of autotrophs, detritus, and prey
Efficiency of energy transfers
NPP
Net sugars from primary producers
In terrestrial ecosystems, how are energy and biomass similar?
Biomass is closely associated with energy production
What happens to the biomass pyramid in aquatic ecosystems
The pyramid is inverted
What is the effect of herbivores being constrained by predators?
they never reach their carrying capacity
trophic efficiency
the amount of energy at one trophic level divided by the amount of energy at thee trophic level immediately below it.
What are the components of trophic efficiency?
consumption efficiency
assimilation efficiency
production efficiency
Consumption efficiency
Proportion of available energy that is ingested
assimilation efficiency
Proportion of ingested food that is assimilated
difference in what is pooped out and what is taken in
Production efficiency
proportion of assimilated food that goes into new consumer biomass
Where is consumption efficiency higher?
in aquatic ecosystems rather than in terrestrial ecosystems
Where else is consumption efficiency higher?
CARNIVORES rather than Herbivores
what is Assimilation efficiency determined by
food quality rather than consumer physiology
Why are endotherms deficient with food?
because we spend so much energy trying to heat our body
What is production efficiency strongly related to?
Thermal physiology and the size of the consumer
Whats the difference between endotherms and exotherms?
They allocate more energy to heat production and have less for growth and reproduction
Bioaccumulation
some chemicals are not metabolized or excreted and become progressively more concentrated in tissues over an organisms lifetime.
biomagnification
concentration of these compounds increases as animals at higher trophic levels, as animals in each trophic level consume prey with higher concentrations of the compounds.