Energy Transfers Flashcards
What is the main route by which energy enters an ecosystem?
Photosynthesis/sun light
What is a producer?
They are photosynthetic organisms and build complex organic compounds during photosynthesis, from light, water, CO2 and minerals. They are the start of the food chain and are autotrophic.
Define autotrophic.
An organism which builds up organic compounds from simple molecules.
Define heterotrophic
An organism that relies on an external source of organic compounds e.g. they have to take in organic compounds.
What is a consumer?
They are heterotrophic. They are mainly animals and consumer plants or other animal to gain organic compounds.
What is a saprobiont?
They are decomposers that break down complex organic compounds in dead organisms. Bacteria and fungi are examples of saprobionts.
Define biomass.
The total quantity or weight of organisms in a given area or volume. Uses gm^-2.
What is a food chain?
They display the feeding relationship between organisms.
What are trophic levels?
They are the levels in a food chain. The arrows in between them display the energy transfer within the food chain.
What is a food web?
They show all the food chains of a habitat linked together as food chains do not occur in isolation. The higher the diversity, the more complex the food web is so a change will not effect it that much.
What are some reasons that energy is lost from the sun to the plant?
Some light is reflected by the atmosphere
Some is the wrong wavelength
Some does not fall on chloroplasts and miss the chlorophyll.
What are some reasons that energy is lost from the plant/animal to the consumer?
Large amounts may be indigestible (e.g. bones and cell walls)
Not all of the plant/animal is eaten
Some energy is lost in excretion e.g. energy lost in urine (heat)
Energy lost in respiration as heat
What % of available sunlight energy is trapped in photosynthesis?
Only 1 to 3% (small)
Energy transfer is ……… and results in large …….. of energy at each trophic level. There is usually no more than ……….. trophic levels as there is too …….. energy to support a breeding population.
Inefficient, losses, 4 or 5, little
What is GPP?
Gross Primary Production is the total chemical energy stored in a given area or volume of a plant at a given time.
