Sunlight - 9th down > Needed to chemically change water...
Population - 10th down > More than one organism of the same species...
Community - 3rd down > Different populations in a specific area...
Trophic Pyramid - 4th down > Shows the energy transfers of populations...
Food Web - 6th down > Shows the feeding relationships of the food chains...
Decomposer - 8th down > Helps dead things to chemically change...