Surface of the corneal epithelium - coloured

Transmission electron micrograph showing surface epithelial cells in a human cornea. A dead surface cell is about to slough away. Below the dead layer is the squamous layer, then the wing cells and towards the lower right are the columnar epithelial cells. A small lymphocyte is present in the wing cell layer and can be distinguished by its small size and large nucleus. Desmosomes appear as dark areas on the cell membranes and function to attach cells to each other and maintain the integrity of the epithelial sheet.