Thick skin is covered by a stratified squamous keratinized epithelium. Small Medium default Large. The epithelial cells form between 10 and 20 layers. The keratin layer is thicker than the cellular layer which is the opposite of thin skin.
Because skin is exposed to air, it is keratinized to protect the surface from abrasion and is lubricated by glycolipids to protect it from dehydration. If we just want to look at stratified squamous keratinized epithelium, we look at skin from one of the few areas of the body that does not have hair.
This tissue is from the palm of the hand palmar skin. The bar shows the thickness of the stratified squamous keratinized epithelium. In this specimen, the epithelium is stained very dark. The lighter areas underneath are connective tissue ct. Stratified squamous keratinized epithelium X Palmar skin. At X you can see the distinct cell layers that make this a stratified epithelium.
The bar indicates the thickness of the stratified squamous keratinized epithelium sske. Cells divide in the basal layer, and move up through the layers above, changing their appearance as they move from one layer to the next.
It takes around weeks for this to happen. This continuous replacement of cells in the epidermal layer of skin is important. The epidermal layer of the skin and digestive tract are the two tissues that are directly exposed to the outside world, and therefore are most vulnerable to its damaging effects.
In both, there is constant proliferation of cells in the bottom layer stratum basale which constantly move up to the top where they are lost. This means damaged cells are continually shed, and replaced with new cells. Find out more about the four different types of cell found in the epidermis. The basal cell layer stratum basale , or stratum germinosum , is a single layer of cells, closest to the dermis. It is usually only in this layer that cells divide.
Some of the dividing cells move up to the next layer.
0コメント