Question: - Food is put into mouth - Food is chewed and mixed with saliva (spit) - Food travels down the esophagus (throat) - Food travels into the stomach - Acid in the stomach breaks the food down further - Food travels into the small intestine - Nutrients from food are absorbed into the blood stream - Food travels into the large intestine - Most of the remaining material is now waste What might be the last step of the process?
Answer: The waste is eventually removed from the body.

Question: - People dig up coal from the ground - People burn coal for heat or electricity - Pollution from the coal goes into the sky - Coal pollution enters clouds - Clouds rain over an area What might be the last step of the process?
Answer: The polluted rain becomes acid rain.

Question: - Acid rain enters the atmosphere and lands - Makes water acidic - Kills fish - Kills the soils in trees What might be the last step of the process?
Answer:
Leaves are also harmed.