Energy transfer pyramids Flashcards
What are autotrophs?
Organisms that synthesise own organic molecules from inorganic molecules - producers
What are photoautotrophs?
Light chemoautotrophs (use light energy)
What are heterotrophs?
They can’t make their own food so depend on autotrophs and digest complex organic molecules into smaller, soluble ones
What are saprotrophs?
They feed on or derive nourishment from decaying organic matter
How does energy move
It is passed up trophic levels from producers to consumers
What occurs at each trophic level?
Great energy loss
Where does producers get energy from?
The sun
Where does energy from grass go?
To the primary consumer, lost by heat from respiration or the energy trapped in the dead remains
Where does energy from the consumer go?
To the next consumer, it is lost by heat from respiration or trapped in dead remains, urine or faeces
Where do detritivores get energy from?
Dead remains, faeces or urine
Where does energy from detritivores go?
It is lost as heat by respiration
What are the types of energy transfer pyramids>
Energy, numbers of biomass
What does a pyramid of energy show?
The energy present at each trophic level
How is energy shown in a pyramid of energy?
The size of blocks represents the proportion of productivity
What does a pyramid of energy look like?
Most energy is available at the 1st trophic level, then 10% of energy is available to the next trophic level
How is energy calculated for a pyramid of energy?
A bomb calorimeter is used to burn sample and work out how much energy is released
What are the strengths of pyramids of energy?
Eliminates most scale and inversion problems
What are the limitations of pyramids of energy?
Biomass may not be equivalent to energy value as 1 gram of material may have a different kJ value, can be inverted if a rapid reproduction rate gives high productivity in a short time as is a snapshot and burning samples isn’t good for rare samples
What are the units of pryramids of energy?
Mass per unit area, such as kg m-2
What do pyramids of numbers show?
The number of organism at each level
What are the limitations of pyramids of number?
Pyramids can be inverted if producer is large, or parasites feed on a consumer and can be difficult to draw difference between numbers of producers and top carnivores can be huge and
What do pyramids of biomass show?
The biomass at each trophic level?
How is biomass shown in pyramids of biomass?
Bars representing mass measured in kg/grams
What do the bars of biomass represent?
The mass of matter lost between each trophic level
