Types of Epithelial Tissue

Types of Epithelial Tissue

• Transitional Epithelium

  • Specialized type allowing stretching, found in the bladder and parts of the urinary tract.

• Simple Squamous Epithelium

  • Single layer of flat cells; facilitates diffusion and filtration; located in alveoli of lungs and lining of blood vessels.

• Simple Cuboidal Epithelium

  • Single layer of cube-shaped cells; functions in secretion and absorption; common in kidney tubules and glands.

• Pseudostratified Columnar Epithelium

  • Appears stratified but is a single layer; often ciliated; found in the respiratory tract, aiding in secretion and movement of mucus.

• Simple Columnar Epithelium

  • Single layer of tall cells; involved in absorption and secretion of mucus and enzymes; lining of the stomach and intestines.

• Stratified Squamous Epithelium (Keratinized)

  • Multiple layers of flat cells; provides protection, particularly in areas exposed to abrasion, such as skin.

• Stratified Squamous Epithelium (Nonkeratinized)

  • Similar to keratinized but lacks surface keratin; found in moist areas such as the mouth, esophagus, and vagina.

• Stratified Columnar Epithelium

  • Multiple layers of cells with columnar shape on the surface; found in male urethra and some glandular ducts.

• Stratified Cuboidal Epithelium

  • Usually two layers of cube-shaped cells; provides protection and is rare, found in some sweat glands and mammary glands.

Key Characteristics

• Epithelial tissues have minimal extracellular material, allowing tight cell connection.
• Serve essential roles in protection, absorption, secretion, and sensation.
• Can be classified by the number of layers (simple vs. stratified) and cell shape (squamous, cuboidal, columnar).