What is the role of decomposers in the cycling of matter in the biosphere?

The decomposers maintain the natural balance of matter during the cycle in which inorganic matter is transformed into organic by the photosynthesis that will pass from one consumer to another in the food chains. When these and the producers die or eliminate of their body the products of waste these substances return to the soil the mineral matter.

The answer is joseph is observing the colour of the reaction mixture to see whether proteins are present in the given solution.