Types of Lining and Covering Epithelium Simple epithelial tissues Simple squamous

♦ Allows for rapid diffusion across the epithelium

Simple Cuboidal
figure 3.1. Types of lining and covering epithelia.

♦ Forms the lining of blood vessels, alveoli of the lungs, and internal body cavities

• Simple cuboidal

♦ Lines and absorbs

♦ Forms the walls of ducts and tubules

• Simple columnar

♦ Lines and absorbs

♦ Forms the lining of the intestines and gall bladder

• Pseudostratified

♦ Cells are of various heights. All cells rest on the basement membrane, but only the tallest cells reach the free surface. Variation in height of the cells and the location of nuclei give the appearance of a stratified epithelium. Frequently ciliated.

♦ Provides protection

♦ Forms the lining of much of the respiratory tract and much of the male reproductive system

^ Stratified epithelial tissues

• Stratified squamous

♦ Protects from physical abrasion and prevents desiccation

■ Nonkeratinized (moist). Lining of wet cavities, including the mouth, esophagus, rectum, and anal canal; surface cells are nucleated and living.

■ Keratinized (dry). Epidermis of the skin; surface cells are nonliving.

• Stratified cuboidal/columnar. Lines the larger ducts of exocrine glands.

• Transitional

♦ Protective function; constructed to expand with distension of the hollow organs it lines

♦ Unique to the urinary system; lines the urinary bladder and ureter

+1 0

Responses

  • taija
    Is the lamina propria in the esophagus the basement membrane?
    8 years ago
  • Kyllikki
    What epithelium forms tubules and ducts?
    7 years ago

Post a comment