Stratified squamous epithelium

Stratified squamous epithelium is a type of epithelial tissue characterized by multiple cell layers, with cells becoming increasingly flattened towards the surface and more cuboidal near the base.

Micrograph of stratified squamous epithelium.

Overview

This type of epithelium is designed for protection, found in areas subject to abrasion or friction. It plays a vital role in defending against microbial and physical assaults.

Structure

The stratified squamous epithelium is composed of several layers:

• Basal layer: Consisting of cuboidal cells, responsible for continual cell production.
• Intermediate layers: Cells start to flatten as they move upwards.
• Surface layers: Composed of flattened, dead cells, often keratinized in areas like the skin.

Locations and Functions

• Skin: Provides a barrier against pathogens, mechanical injury, and fluid loss.
• Oral cavity, esophagus, and vagina: Non-keratinized form, providing a moist, protective layer.

Cell Differentiation and Renewal

Cells in the basal layer continually divide, pushing older cells towards the surface. This process leads to cell differentiation and ultimately the formation of a protective, flattened layer.

Diagram showing layers of the skin, including stratified squamous epithelium.

Pathology

Abnormalities in this epithelium can lead to various conditions, including skin cancer, Psoriasis, and Lichen Planus.

Research and Studies

Ongoing research aims to understand how this epithelium responds to damage and how it regenerates, which is crucial for developing treatments for skin and mucosal diseases.

See Also

• Epidermis
• Keratinization
• Epithelial Tissue in Pathology

External Links

• National Center for Biotechnology Information - Stratified Squamous Epithelium
• Encyclopedia Britannica - Stratified Squamous Epithelium