6.2 - Feeding relationships
Food and energy
● Plants use energy from Sun in photosynthesis → synthesise complex
molecules from simple molecules
● Plants effectively “store” this energy as large molecules in their biomass (生物質)
● Energy can then be released (through respiration)/when another animal eats plant,
energy passed on in biomass
Trophic levels and food chains
● ***Trophic level (營養級): feeding relationship with other organisms in food chain
●
● Energy can also enter food chain when animals (such known as detritivores [有害物
質|食動物]) eat dead plants/animals
○ Play important role in utilising energy originally trapped by living plants
○
● Decomposers - mainly fungi/bacteria, decomposition of dead plants/animals
○ Digesting dead material, through own respiration receiving energy locked
away in plants (then animals) (then transferred through food chain)
○ Break down dead material to single compounds, releasing mineral ions
and CO2
■ The mineral ions and CO2 then become available for plants to use
again (as part of natural recycling processes)
1
Food and energy
● Plants use energy from Sun in photosynthesis → synthesise complex
molecules from simple molecules
● Plants effectively “store” this energy as large molecules in their biomass (生物質)
● Energy can then be released (through respiration)/when another animal eats plant,
energy passed on in biomass
Trophic levels and food chains
● ***Trophic level (營養級): feeding relationship with other organisms in food chain
●
● Energy can also enter food chain when animals (such known as detritivores [有害物
質|食動物]) eat dead plants/animals
○ Play important role in utilising energy originally trapped by living plants
○
● Decomposers - mainly fungi/bacteria, decomposition of dead plants/animals
○ Digesting dead material, through own respiration receiving energy locked
away in plants (then animals) (then transferred through food chain)
○ Break down dead material to single compounds, releasing mineral ions
and CO2
■ The mineral ions and CO2 then become available for plants to use
again (as part of natural recycling processes)
1
