Oesophagus epithelium. Coloured scanning electron micrograph (SEM) of the lining of the human oesophagus or gullet (yellow). The lining is composed of non-keratinised striated squamous epithelial cells, the surface of which are covered in characteristic ridge-like folds (microplicae) that protect against abrasion of rough food. The oesophagus is a muscular tube about 25 centimetres long that runs from the back of the throat to the stomach.