19: Organisms and their environment Flashcards
What is the principal source of energy input to biological systems?
the Sun
Describe the flow of energy through living organisms including light energy from the Sun & chemical energy in organisms and its eventual transfer to the environment
Define a food chain
The transfer of energy from one organism to the next, beginning with a producer
How is energy transferred?
Between organisms in a good chain by ingestion
Define a trophic level
The position of an organism in a food chain, food web, pyramid of numbers or pyramid of biomass
Explain why the transfer of energy from one trophic level to another is inefficient
Explain why food chains have fewer than five trophic levels
Define a food web
A network of interconnected food chains
Define a producer
An organism that makes its own organic nutrients, usually using energy from sunlight through photosynthesis
Define a consumer
An organism that gets its energy by feeding on other organisms
What can consumers be classed as?
Primary, secondary and tertiary according to their position in a food chain
Define herbivore
An animal that gets its energy by eating plants
Define carnivore
An animal that gets its energy by eating other animals
Describe the carbon cycle
What are the effects of the combustion of fossil fuels and the cutting down of forests on the carbon dioxide concentrations in the atmosphere?
