The question is on the picture

To start this off the tree is the producer because green plants make their food by taking sunlight and using the energy to make sugar. The plant uses this sugar, also called glucose to make many things, such as wood, leaves, roots, and bark.. Anyways it serves itself to mainly bugs. Now this caterpillar which is feeding off of the tree is an herbivore and is also called decomposer, organism that breaks down dead organic material; also sometimes referred to as detritivores. The caterpillar takes all that sugar and makes a fine feast. The cardinal is the last one which is the predator for the caterpillar and it's also know as a carnivore and a consumer. It eats the caterpillar and then goes along with it's day

Explanation:

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.