Which organs of the digestive system are classified as "accessory" organs? What is the function of each of these organs in regard to digestion?

Answer 1

Accessory organs (organs outside the digestive tract)—the liver, gallbladder, and pancreas—contribute digestive juices through a common duct into the small intestine. Presence of these digestive juices and enzymes requires ancillary cells that specialize in protecting the digestive system. They do so by secreting a layer of thick, viscous mucus.

Liver
The liver, which produces bile, determines the metabolic fate of every nutrient we digest and absorb, in addition to performing a wide variety of other functions, most of them essential for life.

Gallbladder
The gallbladder is a sac, attached to the liver, where bile is stored and concentrated. Bile empties from the gallbladder into the uppermost part of the small intestine (duodenum) via the common bile duct. Entry of bile into the small intestine is controlled by the sphincter of Oddi.

Pancreas
The pancreas lies behind the stomach and upper portion of the small intestine. The principal functions of the pancreas are exocrine. Bicarbonate and digestive enzymes that act on carbohydrates, proteins, and fats are secreted into the duodenum. Pancreatic amylase breaks down starch and other complex carbohydrates into simpler sugars called disaccharides.