In tanks using a flapper-flush valve, the outlet at the bottom of the tank is covered by a buoyant (plastic or rubber) cover, or flapper, which is held in place against a fitting (the flush valve seat) by water pressure. To flush the toilet, the user pushes a lever, which lifts the flush valve from the valve seat.
Intestines make up the digestive tract. Photo Credit Denis Raev/iStock/Getty Images. Your intestines make up most of your digestive tract. Much of your digestion takes place in your small intestine, while your large intestine absorbs water and excretes waste. Inflammation of the intestines is the primary characteristic of inflammatory bowel diseases, or IBDs, which include Crohn's disease and colitis. Though dietary measures cannot cure IBDs, according to the Crohn's and Colitis Foundation of America, certain foods may support intestinal healing and help alleviate symptoms.
Enzymes from the pancreas help break down the food. The lining of the small intestine is not a straight slippery surface but is wavy so that there is a lot more surface on the inside than on the outside. 1  This surface is covered by villi. 2  These are like tiny fingers.