ANP 1105 Lecture Notes - Lecture 4: Apocrine, Keratin, Bronchus

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: Jacqueline Carnegie

Document Summary

7 special characteristics of epithelial tissue: cellularity, specialized contacts: epithelial cells fit closely together to form continuous sheets. Tight junctions & desmosomes bind adjacent cells together. Tight junctions help keep proteins in apical region of the plasma membrane from diffusing into basal region which helps maintain epithelial polarity: polarity: apical and basal surfaces; differ in structure and function thus exhibit apical- basal polarity. Basal: adjacent to its thin supporting sheet called basal lamina: basal lamina: non-cellular, underlying supportive sheet of primarily glycoproteins. Functions are, acting as a selective filter that determines which molecules diffusing from underlying connective tissue can enter the epithelium. Also acts as scaffolding which epithelial cells can migrate from to repair wounds: supported by connective tissue: all epithelia are supported by connective tissue. For instance, deep to the basal lamina is reticular lamina (extracellular material containing collagen protein fiber) which forms the basement membrane.