Food Chains and Webs Flashcards
What does biomagnification describe?
The magnified effects of pollutants as they travel through the food chain and mainly affect the tertiary consumers
What does bioaccumulation describe?
How substances enter the food chain at the lowest trophic level and effect all organisms in a food chain
What are the four trophic levels from top to bottom?
Tertiary consumers, secondary consumers, primary consumers and producers
Why are there a limited number of links in a food chain?
Because energy is lost at each trophic level
What is energy lost at each trophic level used for?
By the organism for respiration and also lost as heat
What happens when the trophic level of organisms gets higher?
The higher the trophic level of an organism, the greater the energy cost of production of their food
What can human activity on ecosystems cause?
Climate change, permafrost melting, habitat loss and air pollution
What can chemical use within ecosystems cause?
The decline of forests and death of fish and wildlife
What does a food chain demonstrate?
How energy flows between organisms by using a simplistic representation with arrows between organisms
What does a food web demonstrate?
A more complex understanding of the flow of energy in the ecosystem with the arrows meaning ‘is eaten by’ and showing the direction that energy passes within an ecosystem
What does an ecological pyramid demonstrate?
The relative sizes of different components at the various trophic levels in a food chain
What does a pyramid of numbers demonstrate?
The raw numbers of each species at each trophic level per unit area of an ecosystem
What does a pyramid of biomass demonstrate?
The weight of the biological matter at each trophic level
What does a pyramid of energy demonstrate?
The amount of energy input into each trophic level in a given area of an ecosystem
What is the ten percent rule?
When energy is passed on an ecosystem from one trophic level to the next, only ten percent of the energy is passed on
