Thick skin

Layers

Epidermis

The epidermis (skin) consists of stratified squamous epithelium with cornification. It regularly runs into the dermis layer and thus creates epidermal ridges . On the cross-section, we distinguish five layers (layer = stratum ):

  • pp. basale: cubic to cylindrical basophilic elements in a single layer that sit on the lamina basalis. The only intercellular connections are desmosomes
  • pp. spinosum: cubic polygonal elements with cytoplasmic protrusions. We find tonofibrils in them,
  • str. granulosum: basophilic layer with keratohyalin granules (stains intensely dark purple),
  • pp. lucidum: a thin translucent layer, the cells no longer have nuclei or organelles, they are filled mainly with keratin filaments,
  • pp. corneum: anucleate cornified elements.

Pg. basale and str. spinosum are collectively called str. germinativum (germinal layer).

Dermis

The dermis (Slovak suede, Czech skára) develops from the mesenchyme and consists of ligaments that strengthen the epidermis. In some places, it runs into the epidermis and thus creates dermal papillae . It consists of two layers:

  • pp. reticulare: dense connective tissue,
  • pp. papillare: thin ligament.

Hypodermis

The hypodermis (subcutaneous tissue) consists of thin tissue, adipocytes , sweat glands (eccrine – simple coiled tubular glands opening onto the surface of the skin, basally they are surrounded by myoepithelial cells).

References

  • JUNQUIERA, L. Carlos – CARNEIRO, José – KELLEY, Robert O.. Základy histologie. 1. edition. Jinočany : H & H 1997, 1997. 502 pp. ISBN 80-85787-37-7.