What is morphology? The ability to describe a lesion and/or rash (location, size, colour, shape, texture, well or poorly demarcated, morphology (patch, papule), unique features (eg. scarring, collarette)). Layers of the skin. Epidermis - top - keratinocytes. Dermis - collagen - vessels, nerves. Subcutaneous fat. Distribution and morphology important. Derm day.