The columnar cells help in secretion and absorption of materials present in 

Columnar epithelial cells, which are tall and cylindrical in shape, are specialised for secretion and absorption of materials in the intestine. These cells line the surface of the intestinal mucosa and possess numerous microvilli on their apical surface, which greatly increases their surface area for absorption. Additionally, columnar epithelial cells also contain various secretory organelles, such as goblet cells, which secrete mucus to lubricate and protect the intestinal lining, as well as specialized cells that secrete digestive enzymes and hormones. Therefore, columnar epithelial cells play a vital role in the digestive process by facilitating the absorption of nutrients and water from the intestinal lumen into the bloodstream while also participating in the secretion of substances necessary for digestion and maintaining intestinal health.