Why is it said that whether directly or indirectly all living things depends on green plants for food?

All living organisms are inter depend on plants because plants take the food from sun by photosynthesis(auto trophs) and make them as food and animal which eat plants and indirectly take the sunlight and glucose (depend on the plant are called herbivores .The wild animal (carnivores and omnivores) like tiger,lion ,human being take the food from herbivores and these herbivores or carnivores which are died and decomposes in soil ,plant take them as nutrients ,so by these alll living organisms are depend upon plants.