Lab Exercise 5TissuesEpitheliumEpithelial Tissue Distinguishing CharacteristicsFunctions of EpitheliaClassification of EpitheliaSlide 7Slide 8Simple Squamous EpitheliumSlide 10Slide 11Slide 12Slide 13Simple Cuboidal EpitheliumSlide 15Slide 16Slide 17Simple Columnar EpitheliumSlide 19Slide 20Slide 21Stratified Squamous EpitheliumStratified Squamous EpitheliumStratified Squamous Epithelium Non-KeratinizedSlide 25Stratified Squamous Epithelium KeratinizedSlide 27Slide 28Pseudostratified Columnar EpitheliumSlide 30Pseudostratified Columnar Ciliated Epithelium (PCCE)Slide 32Transitional EpitheliumSlide 34Stratified Cuboidal and ColumnarStratified Cuboidal EpitheliumSlide 37Stratified Columnar EpitheliumSlide 39Slide 40Connective TissueConnective Tissue FeaturesConnective Tissue FibersSlide 44Blast cellsCells of Connective Tissue ProperMesenchymeAreolar Connective Tissue (Loose)Slide 49Adipose Tissue (Loose)Reticular Connective Tissue (Loose)Slide 52Dense Regular Connective TissueSlide 54Dense Irregular Connective TissueSlide 56Elastic Connective Tissue (Dense)Slide 58Hyaline CartilageElastic CartilageFibrocartilageBone: Osseous TissueBlood: Hematopoietic TissueThe EndLab Exercise 5Epithelial and Connective TissuesPortland Community CollegeBI 2312Tissues•Groups of cells similar in structure and function•Each tissue is then further subdivided into categories.•All organs are made of a combination of different tissues.•The four types of tissues•Epithelial•Connective•Muscle•NerveEpithelium•Covers all body surfaces, inside and out•Is anchored to connective tissue by a layer of glycoproteins and protein fibers called the basal lamina34Epithelial TissueDistinguishing Characteristics1. Cellularity: Composed almost entirely of cells2. Polarity: apical and basal surfaces (top and a bottom)3. Attachment: Supported by connective tissue (basement membrane)4. Avascular: Contains no blood vessels: obtains nutrients by diffusion 5. Regeneration: Rapidly replaces lost cells by cell divisionFunctions of Epithelia•Protection: Skin•Secretion: glands release secretions•Absorption: Uptake nutrients•Sensory: Taste buds•Filtration: In the kidneys56Classification of Epithelia1. First name:•Simple: one layer•Stratified: more than one layer2. Second name:•Based on the shape of the top layer of cells•Squamous (flat)•Cuboidal (square)•Columnar (rectangle)3. Two additional categories•Transitional•Pseudostratified7Classification of Epithelia8Classification of Epithelia•Squamous•Cuboidal•Columnar9Simple Squamous Epithelium•Single layer of flattened cells with disc-shaped nuclei and sparse cytoplasm10Simple Squamous Epithelium•Top View1112Simple Squamous Epithelium13Simple Squamous Epithelium•Functions: 1. Diffusion•Alveoli in the respiratory system allows for exchange of O2 and CO22. Filtration•Capillaries allow fluid and other substances out and holds blood cells and proteins in3. Lubrication•Secretes lubricating substances in serosae14Simple Cuboidal Epithelium•Single layer of cube like cells with large, spherical central nuclei1516Simple Cuboidal Epithelium17Simple Cuboidal Epithelium•Functions:1. Secretion•Glands such as the thyroid are composed of simple cuboidal epithelium and secrete hormones ect…2. Absorption•In the kidney, the proximal convoluted tubule is composed of simple cuboidal epithelium and reabsorbs water and other nutrients from the filtered fluid18Simple Columnar Epithelium•Single layer of tall cells with oval nuclei toward the basal surface•Goblet cells are often found in this layer19Simple Columnar Epithelium20Simple Columnar Epithelium21Simple Columnar Epithelium•Functions1. Secretion•Example: In the stomach, these cells secrete digestive enzymes2. Absorption•Example: In the intestine, these cells absorb nutrients22Stratified Squamous Epithelium•Composed of several layers of cells•Top layer flat•Bottom layers any shape•Function in protection of underlying areas subjected to abrasion23Stratified Squamous Epithelium•Non-keratinized•Composed of several layers of cells•Top layer flat•Bottom layers any shape24Stratified Squamous EpitheliumNon-Keratinized25Stratified Squamous EpitheliumNon-Keratinized•Functions1. Physical protection against abrasion and pathogens•Non-Keratinized is associated with “moist” areas•Mouth•Throat•Esophagus•Anus•Vagina26Stratified Squamous EpitheliumKeratinizedLooks “flakey” on the top27Stratified Squamous EpitheliumKeratinized28Stratified Squamous EpitheliumKeratinized•Functions1. Physical Protection•Found only in the epidermis of the skin•Keratin is a protein that helps strengthen the cells against abrasion29Pseudostratified Columnar Epithelium•Single layer of cells with different heights; some do not reach the free surface•Nuclei are seen at different levels•May be ciliated (PCCE) or non-ciliated30Pseudostratified Columnar Epithelium31Pseudostratified Columnar Ciliated Epithelium (PCCE)32Pseudostratified Columnar Ciliated Epithelium (PCCE)•Functions1. Protection•Example: Lines the upper respiratory tract. The cilia sweep debris toward the throat2. Secretion•Example: May contain goblet cells (unicellular glands) that secrete mucus33Transitional Epithelium•Several cell layers, basal cells are cuboidal•Apical cells are dome shaped when not stretched•Apical cells are flat when stretched•Only found in Urinary System•Functions:1. Allows expansion and recoil after stretching34Transitional EpitheliumDistended bladder Empty bladder35Stratified Cuboidal and Columnar•Typically two cell layers thick•Rare•Functions:1. Secretion•Found in some sweat and mammary glands36Stratified Cuboidal Epithelium37Stratified Cuboidal Epithelium38Stratified Columnar Epithelium•Limited distribution in the body•To tell the difference between this and pseudostratified columnar, look at the nucleus.•The nuclei are lined up in a straight row •Function1. Protection•Found in the pharynx, male urethra, lining some glandular ducts, and anus39Stratified Columnar Epithelium40Stratified Columnar Epithelium41Connective Tissue•4 Types1. Connective Tissue Proper2. Bone3. Blood4. Cartilage42Connective Tissue Features1. Specialized cells2. Matrix: Nonliving material between the cells that makes up most of the volume (ground substance + fibers)•Extracellular fibers•Ground substance: Composed chiefly of interstitial fluid, cell adhesion