I have to go to the bathroom. But why? How does my body do this?
Well, when food first enters the body it goes through my mouth where my teeth us mechanical digestion to chomp and grind my food. Then saliva in the mouth (an enzyme) uses chemical digestion to break down the food even more. Once that is done I use my tongue to swallow my food.
After that, the food goes down the esophagus and peristalsis within it help push the food down to the stomach where the food is broken down more into a liquid called chyme. near the stomach is the pancreas. In the pancreas the are enzymes made to break down starches like potatoes. Near there connected to the liver is the gallbladder which also produces an enzyme to break down proteins.
After the stomach has done its part the food travels on to the small intestine. This is where most of the digestion takes place and small villi take the nutrients from the food and supply it to the bloodstream.
Then the food makes its way to the large intestine which is actually smaller than the large intestine in the length but larger in width. Here the water leaves the digestive system and it moves undigested waste to the rectum where it is stored and eventually your stool.
This lengthy process can take up 1-2 days. So if you think about even if you're not doing anything your digestive system is!