Our digestive system does the opposite of an assembly line. Instead of getting complex and bigger, they are broken down into smaller pieces by mechanical and chemical processes in our digestive tract.
Explanation:
Food is first broken down mechanically in our mouths. Then chemicals in the stomach digest the food further. There also is mechanical digestion in this section of the digestive tract. As the food descends, more nutrients are absorbed in the intestines, in this areas the contraction of the muscles helps to move the processed food up to the end of the "assembly line" where the product is less complex than it used to be since the nutrients are now in our body.
