Explanation

Duodenum of small intestine possesses Brunner’s gland, which secretes large amount of mucous and bicarbonates, which in turn, proteins, the duodenal mucosa and neutralises the acidic chyme. It also secretes two hormones, secretin and cholecystokinin. However, secretin is secreted by duodenal wall and cholecystokinin is secreted by the epithelium of small intestine