ANP 1105 Chapter Notes - Chapter 4.2: Acinus, Brush Border, Bronchus

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: Frank Feiner

Document Summary

Epithelial tissue: sheet of cells that covers/lines a body surface. Covering/lining epithelium: outer layer of skin, lines open cavities & covers walls/organs of the closed ventral cavity. The main functions of epithelium are (6) protection, absorption, ltration, excretion, secretion & sensory reception. Polarity: the two surfaces of the epithelium (apical & basal) differ in structure and function . :. Apical surface: some are smooth/slick, most have microvilli (described as a brush border) or cilia. Basal surface: consists of basal lamina (consists of glycoproteins & collagen bres), this layer is selectively permeable and acts as a scaffolding for epithelial cells to repair wounds. Specialized contacts: the sheets of epithelial cells make lateral contacts (tight junctions & desmosomes); these closely packed cells prevent proteins from diffusing into the basal region this maintains epithelial polarity. Reticular lamina: under basal; has a layer of extra cellular material containing a ne network of collagen proteins bres that are a part of the connective tissue.