I believe the answer is DIGESTION , I think this because when your food is going through the process of digestion, there is physical and chemical breakdowns of your food, and the nutrients that comes from the food you ate.
Mouth: physical digestion
Stomach: chemical digestion
Small Intestines: helps break down the food more after it absorbs the nutrients from the food into the blood stream
Large Intestines: absorbs the remaining water from the food into the bloodstream/body
Hope this helped :)