Supported by the Savannah and Barry French Poodle Memorial Fund
University of Pennsylvania School of Veterinary Medicine
Last Modified: August 21, 2005
Michael H. Goldschmidt, MSc, BVMS, MRCVS, Diplomate ACVP Professor and Head, Laboratory of Pathology and Toxicology Chief, Surgical Pathology Department of Pathobiology
Frances S. Shofer, PhD, Adjunct Associate Professor of Epidemiology and Biostatistics
The skin, or integument, is the largest organ of the body.
It consists of 3 layers:
The skin protects the body from the external environment. It is a dynamic organ that responds rapidly to changes.
The epidermis is the outer skin layer of the skin and consists of two types of cells:
Keratinocytes are the major component of the epidermis and are so called because they produce the intracellular protein keratin (keratinization).
The epidermic is divided into 4 layers:
The movement of the epidermal cells from the stratum basale to the stratum corneum is a dynamic process involving:
Melanocytes and Merkel cells reside in the stratum basale, Langerhans cells are in the stratum spinosum.
The dermis is made up of:
The adnexa (see above) are found in the dermis with an intimate association with the overlying epidermis.
Panniculus adiposus is made up of: