Final answer:
The submucosal glands of Brunner are found in the duodenum of the small intestine. They produce a bicarbonate-rich alkaline mucus to buffer the acidic chyme from the stomach. These glands are located in the submucosa layer.
Step-by-step explanation:
The submucosal glands of Brunner are found in the duodenum, which is the first part of the small intestine. These glands, also known as Brunner's glands, produce a bicarbonate-rich alkaline mucus that helps to buffer the acidic chyme (partially digested food) as it enters from the stomach. They are located in the submucosa, which is a layer of connective tissue beneath the mucosa.