LAB 2 EPITHELIUM Jakoi 2014

Three epithelial cell shapes and two types of layering (simple and stratified)

TO IDENTIFY, DETERMINE: 1. Shape: squamous, cuboidal, columnar – must ID from outermost layer of cells2. Layering: simple, stratified, pseudostratified,

transitional (outermost cells are pillowy to flat – change with distension of organ; only in urinary tract!)

3. Modification: if stratified squamous must say keratinized or non-keratinized If columnar must ID apical specialization - microvilli? cilia? stereocilia?

FUNCTION OF EPITHELIIUM:Sheet of cells that lines a free surfacePolarized cells: apex vs base, outer surface is free surface; inner surface faces basal lamina (CT)Section views: en face (looking down on outer surface); transverse; oblique

VOCABULARY:MesotheliumEndotheliumLumenCuboidal, columnar, squamous Stratified epithelium, simple epithelium, transitional epitheliumMicrovilli (brush border), cilia, stereociliaTerminal web, terminal bars, basal bodiesKeratinizedGoblet cell

Transitional