By: Justin and Douglas
The mouth is a complicated mechanism for tearing, cutting, and grinding food into small pieces ready for digestion.
Salivary glands produce a watery mixture of mucus and enzymes. This lubricates chewed food and begins the digestion of carbohydrates. Many small salivary glands are dotted throughout the cheeks.
The muscular esophagus pushes food and drink along by peristalsis. It works just as effectively if you stand on your head, or even if there is no gravity as in a spacecraft.
The stomach is extremely muscular. It can stretch to hold large amounts of food.
This is what happens to a piece of food that enters your mouth:
Food passes down the throat, down through a muscular tube called the esophagus, and into the stomach, where food continues to be broken down by many juices. Just like a washing machine!
The partially digested food passes into a short tube called the duodenum (first part of the small intestine). The jejunum and ileum are also part of the small intestine. The liver, the gallbladder, and the pancreas produce enzymes and substances that help with digestion in the small intestine.
The last section of the digestive tract is the large intestine, which includes the cecum, colon, and rectum. The appendix is a branch off the large intestine; it has no known function. Indigestible remains of food are expelled through the anus.
Label the digestive system
Human digestion system