Living things all share several common characteristics. Which of the following characteristics do all living things share? they all reproduce, they all create energy
they are all made of cells, they all reproduce
they all have DNA, they all reproduce sexually
they all grow and develop, they all create energy

1. The digestive system fuels the cells and excretory system rids the body of cell waste.

The digestive system breaks down the food into simple components like sugars which can be taken up by cells as a fuel to conduct cellular metabolism. Without digestive system food cannot be split into forms utilized by cells. During the process of respiration it is ensured that essential food components should be absorbed completely but this does not happen as some of the part cannot be absorbed by the cells which can be considered as  cellular waste and should be removed. This cellular waste is removed by the excretory system. Therefore, excretory system provides the rid from cellular waste.