Nat 5 Biology Unit Three Life On Earth Key Area 4 Energy in ecosystems Flashcards
How is energy lost in the is energy lost in the food chain?
As heat, by movement an in undigested materials
How much energy is retained and how much is lost in the food chain?
90% of energy is lost, 10% retained
Growth (10%)
Undigested materials (60%)
Heat and movement (30%)
What does a Pyramid of Numbers do?
It represents the number of organisms at each trophic level.
Producers at the base, Primary consumers above, followed by secondary consumers and tertiary consumers at the top. The length of each bar proportional to the number of individuals at the level.
A Pyramid of Numbers may have an irregular shape when the number producers is less than the number of props art consumers e.g. One Oak tree feeds on hundreds of Aphids and Caterpillars etc.
What does a Pyramid of Energy show?
It shows the quantity to energy stored in the biomass of the organisms at each level in the food chain. Because energy is always lost between each level of food chain, a Pyramid of Energy always has a regular pyramid shape.
