I dont know thats why i asked!
an energy pyramid
Is a model that shows how much energy is available at each level of a food chain or ecosystem
Some energy is lost at each level since not all energy is transferred from the food to the consumer.
Because each consecutive levels contains fewer organisms than the level below
idont know
a food web
As energy flows through the food chain, 90% of the energy is lost at each trophic level and 10% is passed on.
it goes through trophic levels (which is each level of the pyramid ot web or chain) The energy changes from each trophic level
By bottom, do you mean where the food chain starts(with plants) then YES :) only 10% passes on to each level :)
The trophic levels show which organisms are at each level of the energy pyramid. The pyramid is shaped exactly as a pyramid. The lowest level contains the most energy and the most in number and variation of species. The next level only has 10% of the first levels' energy and fewer species. The amount of energy in the first level determines the number of levels possible. The tropical rain forest has the most levels (as many as 4) and a desert has the fewest (as few as 2). See links below:
Energy Pyramid
It depends on the activity of the animal in question but it is usually around 10%.