Transfers of energy and matter Definitions Flashcards
Open systems
systems where resources can enter or exit, including both chemical substances and energy
Closed systems
systems where energy can or exit, but chemical resources cannot be removed or replaced
Producers
organisms that use an external energy source(e.g. Sun) to make carbon compounds
Consumers
organisms that feed on other organisms(e.g. plants, animals, etc.) to get energy
Food chain
a sequence of organisms, each of which feeds on the previous organism
Trophic level
the position an organism occupies in the food chain
Food web
a model that summarizes all of the possible food chains in a community
Defecation
the removal of faeces from the gut
Moulting
the process by which an animals casts of parts of its body to serve some beneficial purpose
Carbon fixation
the process by which autotrophs convert(i.e. fix) atmospheric carbon to form organic compounds
Autotrophs
organisms that use external energy sources to synthesize carbon compounds from simple inorganic substances
Photoautotrophs
organisms that use sunlight to synthesize carbon compounds by photosynthesis
Chemoautotrophs
organisms that use exothermic inorganic chemical reactions(i.e. chemosynthesis) to synthesize carbon compounds
Heterotrophs
organisms that obtain carbon compounds by consuming other organisms
Assimilation
the process of absorbing nutrients(e.g. carbon compounds) and making them part of the body
Endocytosis
an acitve transport process where cells engulf external materials to incorporate them into their internal environment
Phosphorylate
to add a phosphate group to(a molecule or compound)
Pyramid of energy
a graphical represenation of the amount of energy at each trophic level of a food chain
Production(in ecosystems)
the accumulation of carbon compounds in biomass
Primary production
the mass of carbon compounds synthesized from CO₂ and other simple substances by autotrophs(producers)
Gross primary production(GPP)
the total biomass of carbon compounds made by plants(and other autotrophs)
Net primary production
Gross primary production(GPPP) minus the biomass lost due to respiration of the plant; the amount of energy left available to consumers
Secondary production
the accumulation of carbon compounds in biomass by animals and other heterotrophs
Pool
the reserve of an element(e.g. carbon)
