Transcript energy flows through an ecosystem

Photosynthesis: use of chlorophyll. Energy storing
process.
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6 CO2 + 6 H2O + solar energy  C6H12O6 + 6 O2
Cellular Respiration:
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Aerobic Respiration: energy releasing process.
C6H12O6 + 6 O2  6CO2 + 6 H2O + energy (ATP)
Anaerobic Respiration
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Ex. Fermentation: energy releasing process used by
yeast and bacteria
ENERGY IS LOST AT EACH TRANSFER
 The chemical energy in sugars from sunlight energy
trapped by producers is used mainly by the
producers themselves for staying alive. A small
amount of this energy is available to consumers in
the ecosystem.
 Energy used by producers through the process of
cellular respiration and is lost as heat.
ENERGY IS LOST AT EACH TRANSFER
What is the estimated percentage of radiant energy,
captured by producers, that is used for producers own
maintenance?
 Most of the chemical energy taken by a herbivore is
used for its own maintenance. Only a small fraction is
available for flow on to carnivores.
2. Where does the lost energy go?
 Because of the loss of energy occurring at each trophic
level, there is a limit to the number of transfers through
trophic levels in an ecosystem.
1.
3. Explain the ‘rule of thumb’ for calculating the transfer
of chemical energy between trophic levels.
 Food
webs and food chains show the energy
transfers or energy flow in an ecosystem by
indicating specifically who eats whom.
Arrows show the direction of transfer but not
the chemical energy at each transfer.
 Food chains are less complex and often do
not show energy flow from dead organisms
Food Chains
Food chains are a simple food path involving a sequence
of organisms, each of which is the food for the next.
Food Webs
Food webs are multiple food
chains that are interconnected.
More complex than food
chains.
ENERGY FLOW
Summarise the 3 main conclusions
regarding energy lost as heat at each
trophic level
2. Explain how humans can exist at
different trophic levels.
1.