Goblet cell. Transmission electron micrograph (TEM) of a section through a goblet cell in the lining (epithelium, top) of the small intestine, showing mucous being discharged (upper centre) onto the surface of the epithelium. Mucous is rich in carbohydrates and, following release from the goblet cell, becomes hydrated and expands enormously in volume forming a gel-like layer over the surface of the epithelial cells. This protects the epithelium and traps cell debris and particles that are not digested. Magnification: x11,000, when printed 10 centimetres wide.