What is the definition of an accessory organ of the digestive system? List them

Accessory organs of the digestive system are not physically part of the gut tube that stretches from the mouth to the anus. They are attached to the gut tube by a duct. The accessory organs are the salivary glands, liver, gallbladder, and pancreas.
   • Salivary glands: contain water, lubricants, amylase to soften food; make it easier to swallow and to begin carbohydrate digestion
   • Liver: secretes bile to emulsify fats
   • Gallbladder: stores bile for the liver
   • Pancreas: secretes buffers to neutralize acidic chyme leaving the stomach and digestive enzymes to digest carbohydrates, lipids, and proteins