Brunner's glands are specialized glands located in the submucosa of the duodenum, which is the first part of the small intestine. Their primary function is to secrete an alkaline fluid that helps to neutralize stomach acid as it enters the small intestine. This alkaline secretion also provides an optimal environment for digestive enzymes to function effectively. In addition to neutralizing acid, Brunner's glands produce mucus that lubricates the intestinal lining, aiding in the smooth passage of food. These glands are particularly important for protecting the intestinal wall from damage caused by acidic chyme and ensuring efficient digestion and absorption of nutrients.