Epithelial Tissue

Epithelial Tissue

1. Cells with additional features

   • Cilia
     • Tiny hair like projections e.g. found in the female reproductive tract- to help move the ovum along the tract and upper respiratory tract- to move dust, mucous etc.
   • Microvilli
     • Tiny folds in membrane, increase surface area for absorption, found in small intestines, under a microscope they look like tiny brushes
   • Goblet Cells
     • A mucous cell found in the epithelium of mucous membranes, secrete mucous onto tissue surfaces, e.g. in respiratory passages and intestines

2. Stratified epithelium

   • Cnsists of two or more cell layers and had a protective function
   • Stratified Squamous Epithelium
     • Base cell divides rapidly
     • As they get further away from the blood supply they begin to degenerate and the cells flatten
     • Cells migrate through the layers
     • Cells at the surface are usually dead and flake off in response to friction over the surface
     • In skin the top cells are impregnated with keratin, a protein that is waterproof and makes the cell more robust
     • The tissue is found on surfaces that are subject to abrasive force e.g., skin and parts of the digestive system

3. Transitional Epithelium