Accessory Organs

Accessory Organs

The organs discussed above are the organs of the digestive tract through which food passes. Accessory organs add secretions and enzymes that break down food into nutrients. Accessory organs include the salivary glands, the liver, the pancreas, and the gall bladder. The secretions of the liver, pancreas, and gallbladder are regulated by hormones in response to food consumption.

The liver is the largest internal organ in humans and it plays an important role in digestion of fats and detoxifying blood. The liver produces bile, a digestive juice that is required for the breakdown of fats in the duodenum. The liver also processes the absorbed vitamins and fatty acids and synthesizes many plasma proteins. The gallbladder is a small organ that aids the liver by storing bile and concentrating bile salts.

The pancreas secretes bicarbonate that neutralizes the acidic chyme and a variety of enzymes for the digestion of protein and carbohydrates.

Art Connection
Illustration shows the human lower digestive system, which begins with the stomach, a sac that lies above the large intestine. The stomach empties into the small intestine, which is a long, highly folded tube. The beginning of the small intestine is called the duodenum, the long middle part is called the jejunum, and the end is called the ileum. The ileum empties into the large intestine on the right side of the body. Beneath the junction of the small and large intestine is a small pouch called the cecum. The appendix is at the bottom end of the cecum. The large intestine travels up the left side of the body, across the top of the small intestine, then down the right side of the body. These parts of the large intestine are called the ascending colon, the transverse colon and the descending colon, respectively. The large intestine empties into the rectum, which is connected to the anus. The pancreas is sandwiched between the stomach and large intestine. The liver is a triangular organ that sits above and slightly to the right of the stomach. The gallbladder is a small bulb between the liver and stomach.

The stomach has an extremely acidic environment where most of the protein gets digested. (credit: modification of work by Mariana Ruiz Villareal)