Energy And Ecosystems Flashcards
what do plants do in any ecosystem?
- plants synthesise organic compounds from atmospheric, or aquatic, carbon dioxide
what are most of the sugar synthesised by plants used for?
- used by the plant as respiratory substances
what is the rest of the sugar synthesised by plants used for?
- used to make other groups of biological molecules
what do the biological molecules form?
biomass of the plants
what happens during photosynthesis?
- light energy is transferred to chemical energy
where is the chemical energy from photosynthesis primarily stored?
- the biomolecule that photosynthesis produces
- in the covalent bonds of the molecule (C-C and C-H bonds)
how can biomass be measured?
- mass of carbon
- dry mass of tissue per given area
how can the chemical energy store in dry biomass be estimated?
using calorimetry
what is the gross primary production(GPP)?
the chemical energy store in plant biomass, in a given area or volume
what is net primary production(NPP)?
the chemical energy store in plant biomass after respiratory losses to the environment have been takin into account
how is NPP calculated?
NPP = GPP - R
NPP = net primary production
GPP = gross primary production
R = respiratory losses to the environment
what is net primary production available for?
- plant growth
- reproduction
- to other trophic levels in the ecosystem (e.g. herbivores and decomposers)
what are trophic levels?
- levels in the food chain
how do consumers gain chemical energy?
through digestion
how can the net production of consumers be calculated?
N = I - (F+R)
I = chemical energy store in ingested food
F = chemical energy lost to the environment in faeces and urine
R = respiratory losses to the environment
