Human skin. Light micrograph of a section through healthy human skin. The outer surface of the skin is at top. The uppermost surface is the epidermis, which is topped by the dead stratum corneum layer. Cells are continually shed from this layer and are replaced by cells from the living underlying layer, the stratum germinativum (purple). This layer lies on top of the dermis, the thickest skin layer, which contains hair follicles (for instance down left), a sebaceous gland (white, right of follicle), sweat glands (purple/white, lower right) and blood vessels. The body of the dermis comprises fatty and connective tissue. Magnification: x37 when printed 10cm high.