The main organs of the human digestive system process the food that you eat so that it can be turned into smaller bits that in turn are further broken down into molecules. It is, in essence, a series of tubes that each have a specific function.
The human digestive tract takes in food in various forms, extracts from this food source the nutrients that the body turns into energy, and then excretes the waste products. The stomach is where food is broken down by gastric acid and digestive enzymes after it comes down the esophagus. Digestion of food takes place mainly in the small intestine, where vitamins and nutrients are absorbed. It then passes through the large intestine, which compacts the waste and stores any water left over from the small intestine. Waste is finally gotten rid of through the anus at the end of the digestive system after being stored in the rectum. Other organs such as the liver, pancreas and gall bladder are instrumental in secreting and storing substances that aid in the breakdown of food.
The digestive tract is also known as the alimentary canal and consists of what is known as an upper gastrointestinal tract and a lower GI. The upper is composed of the mouth, pharynx, esophagus, and the stomach while the lower is made up of the bowels, the small and large intestines and the anus. These are the main organs of the digestive system.
The human stomach is a "J" shaped, hollow organ. It is connected to the mouth by the esophagus, which looks like a muscular tube. From the stomach, the food is absorbed into the small intestine, which is covered with microscopic projections that aid in the absorption of nutrients and secreting enzymes. The small intestine is wrinkled and compact despite its length. The large intestine wraps around the small intestine in a shape resembling the letter "U" upside down.
The average human small intestine is almost 23 feet in length. The large intestine is 5 feet long, but gets its name because it is wider in diameter than the small intestine. The stomach has the ability to hold between 2 to 4 liters of food when it expands and is able to produce up to 3 liters of gastric acid in a day.
One of the biggest misconceptions about any disease to the human body involves the digestive system, specifically the stomach. Ulcers have been incorrectly thought to stem from eating spicy foods or enduring too much stress. However, the real cause of ulcers is a bacterial infection, with some being brought about by smoking or reaction to some medications.