8/26/20141Mastering A&P: common questions• You must select that our course is using 7thed in order to have access to the course• If you are using an access code that came packaged w/ the textbook, it must be from a 7thedition textbook• You can use any e-mail to set up your login- you will enter your student ID when you get to the course page• Course ID needed to get to page is: MAPHEISLER46266• Make sure you are using the best browser & settings! On Mastering log-in page, go to:Support & Training  System requirementsWhen are homework assignments due?A. Every Sunday at 11 pmB. Every Friday at 9 amC. Every Monday at 11 pmD. Every Saturday at midnightE. Every Wednesday at noonTISSUES:EpitheliumA covering or lining8/26/20142Human Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Figure 4.1 Special characteristics of epithelium.EpitheliumConnectivetissueApical region Basal regionNarrow extracellular spaceCell junctions 1. Cellularity little extracellular space2. Cell junctionsabundant; strength & communication3. Polarity  distinct apical & basal surfacesHuman Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Figure 4.1 Special characteristics of epithelium.EpitheliumConnectivetissueApical region Basal regionBasallamina Reticularfibers BasementmembraneNerve endingCapillary in underlying tissueNarrow extracellular spaceCell junctions 4. Sits on basement membrane support5. Avascular6. Innervated7. Regeneration high capacity to replace cells Human Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Figure 4.1 Special characteristics of epithelium.EpitheliumConnectivetissueTight junctionGap junctionDesmosomeCell junctionsLATERAL WALL SURFACE FEATURES8/26/20143Human Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Figure 4.1 Special characteristics of epithelium.EpitheliumConnectivetissueBasal regionBasallamina Reticularfibers BasementmembraneNerve endingBASAL SURFACE FEATURESBasal lamina  non-cellular sheet of proteins; provide surface for new cells to build onBasement membrane = basal lamina & reticular fibers of underlying CTHuman Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin Cummings.Figure 4.1 Special characteristics of epithelium.EpitheliumConnectivetissueApical regionCiliaMicrovilliAPICAL SURFACE FEATURES1. Microvilli  folds of plasma membrane of moist epithelial tissue• Maximize surface area for absorption2. Cilia  whiplike, motile extensions of cell surface; found in some locations• Movement of mucusHow might microvillar extensions from the apical surface of epithelial cells be advantageous to the cell?A. They allow the cell to move more easily through tissues.B. They allow for stronger attachment to the basal lamina.C. They thicken the plasma membrane to provide more protection.D. They increase the surface area to allow for the transport of more ions into the cell.8/26/20144Membranous vs Glandular epitheliumMembranous: majority of body coverings and linings (will focus on)Glandular: specialized epithelial tissue that produces glandular secretionsMAJOR DIFFERENCE?? LOCATION….Organization of an epithelial tissue directly related to the functionPrimary functions associated w/ epithelial tissues:• Protection• Absorption• Filtration• Diffusion• ChemoreceptionSkinSmall IntestineKidneyLungsNasal cavity (smell)What changes would you make to an epithelial tissue to allow for these different functions?Fig. 4.2a Classification of membranous epitheliaSIMPLE1 cell layer thickSTRATIFIED>1 cell layer thick8/26/20145Fig. 4.2b Classification of epitheliaFig. 4.2b Classificiation of epitheliaSQUAMOUS Flattened cellsCUBOIDALCube shaped cellsCOLUMNARTall cellsWhat would you expect a stratified cuboidal epithelium to look like?A. One layer of cube shaped cellsB. Multiple layers of cube shaped cellsC. One layer of flattened cellsD. Two layers of column shaped cellsE. Multiple layers of flattened cellsWhat would you call an epithelium that looked like this:A. Stratified columnar cuboidal squamousB. Simply stratifiedC. Stratified columnarD. Simple columnar cuboidal squamousE. Stratified squamousBasement membraneApical surface8/26/20146Stratified epithelia are named by the cell shape found on the apical surfaceFig 4.3a Simple squamous epithelium• Single layer of flattened cells• Diffusion  lungs• Filtration kidney• Secretion serous membranesFig. 4.3b Simple cuboidal epithelium• Single layer of cube shaped cells• Absorption kidney• Secretion  some glands8/26/20147Fig. 4.3c Simple columnar epithelium• Single layer of tall cells• May or may not be ciliated….• Absorption  GI tract• Movement ie of mucus (lungs)• Secretion  mucusFig. 4.3d Pseudostratified columnar epithelium• Single layer of cells of varying height• ALL sit on basement membrane• Secretion & movement mucus of respiratory system• Usually ciliated….Stratified epithelia• 2 or more cell layers• Basal layer germinating layer• Apical layer  oldest cells• Named by shape of apical layer of cells8/26/20148Fig. 4.3e Stratified squamous epithelium• Multiple cell layers, apical layer flat• Keratinized or non-keratinized• Protection skin, oral cavityFig. 4.3f Stratified cuboidal epithelium• Two layers cube shaped cells• Protection glandular ducts (iesalivary ducts)Fig. 4.3g Stratified columnar epithelium• Several cell layers; apical layer tall• Not common• Protection male urethra• Secretion  some glands8/26/20149Fig. 4.3h Transitional epithelium• Multiple layers that change shape when stretched• Unique allows bladder to expand as it fills w/ urineTypes of glandsAll glands lined by an epithelium1. Endocrine: lack ducts, produce hormones which pass into surrounding tissues/blood vessels2. Exocrine: secrete via ducts into body cavities or onto body surfaceThyroid & parathyroid glandsExocrine glandsDucts can be:SIMPLE  unbranchedCOMPOUND branchedGland can be:TUBULAR tube shapedALVEOLAR  rounder/orb shaped8/26/201410Human Anatomy, 5eby Marieb, Mallatt, and WilhelmCopyright © 2008 Pearson Education, Inc.,publishing as Benjamin