History to lesson 6 lecture

• Epithelial tissues


  Formed of epithelial cellsProvided with basement membrane<|>Cohesive and relatively strong<|>Avascular<|>Derived from three germ layers
• Embryonic germ layers


  • Ectoderm (outer layer)
  • Mesoderm (middle layer)
  • Endoderm (inner layer)
• Fundamental types of tissues

  • Epithelial tissue
  • Connective tissue
  • Muscular tissue
  • Nervous tissue
  • Hematopoietic tissue
• Function of epithelial tissues

  Covering, lining, and protecting surfaces<|>Absorption<|>Secretion
• Two general classifications of epithelial tissues

  • Covering epithelium
  • Glandular epithelium
• Types of simple epithelium

  • Simple squamous epithelium
  • Simple cuboidal epithelium
  • Simple columnar epithelium
• Simple squamous epithelium


  Facilitates the movement of the viscera (mesothelium), active transport by pinocytosis (mesothelium and endothelium), secretion of biologically active molecules (mesothelium)
• Locations of simple squamous epithelium

  • Endothelium of blood vessels
  • Mesothelium of body cavities
  • Thin loop of Henle
  • Bowman's capsule
• Locations of simple columnar epithelium

  • Gastrointestinal system
• Locations of simple columnar ciliated epithelium

  • Uterus / Fallopian tube
• Types of stratified epithelium

  • Stratified squamous epithelium
  • Stratified cuboidal epithelium
  • Pseudostratified columnar epithelium
• Stratified squamous epithelium


  Uppermost layer is flattened, intermediate layer is polyhedral, innermost layer is columnar
• Types of stratified squamous epithelium

  • Stratified squamous keratinized epithelium
  • Stratified squamous non-keratinized epithelium
• Stratified cuboidal epithelium


  Uppermost layer is cuboidal cells, underlying layer is polyhedral cells
• Stratified columnar epithelium


  Uppermost layer is columnar cells, underlying layer is polyhedral cells
• Pseudostratified epithelium


  Appears stratified but is actually a single layer of cells of varying heights
• Transitional epithelium


  Cells change shape as the bladder fills and empties
• Glandular epithelium


  Function is to synthesize, store, and secrete proteins, lipids, carbohydrates and protein complexes
• Classification of glands by number of cells

  • Unicellular gland
  • Multicellular gland
• Manner of secretions


  • Exocrine
  • Endocrine
• Types of secretions


  • Serous
  • Mucus
• Locations of mucous-serous glands

  • Submandibular & Sublingual Gland
• Cytogenic gland


  Produces cells
• Morphology of glands


  • Simple tubular
  • Simple coiled tubular
  • Simple branched tubular
  • Simple acinar
  • Simple branched acinar
  • Compound tubular
  • Compound tubulo-alveolar
  • Compound alveolar
• Locations of simple branched tubular glands

  • Uterine glands
  • Gastric glands
• Locations of simple branched acinar glands

  • Large sebaceous gland of the skin
  • Meibonian glands of the eyelid
• Locations of compound tubular glands

  • Pure mucous gland of oral cavity
  • Cardiac gland of stomach
  • Some Brunner's glands
  • Bulbourethral glands
  • Renal tubules
• Locations of compound alveolar glands

  • Some portions of the mammary gland
• Connective tissues provide support, binding, protection, fat storage, insulation, hematopoiesis, infection protection, and repair
• Components of connective tissue

  • Connective tissue cells
  • Ground matrix
  • Connective tissue fibers
• Types of connective tissue cells

  • Fixed cells
  • Free cells
• Fixed connective tissue cells

  • Fibroblasts
  • Mesenchymal cells
  • Reticular cells
  • Fat cells / adipocytes
• Free connective tissue cells

  • WBC
  • Mast cells
  • Plasma cells
  • Macrophages
• Ground matrix


  Amorphous ground substance composed of acid mucopolysaccharides or glycosaminoglycans
• Types of glycosaminoglycans


  • Hyaluronic acid
  • Chondroitin sulfate
  • Dermatan sulfate
  • Keratan sulfate
  • Heparan sulfate
• Types of connective tissue fibers

  • Collagen fibers
  • Elastic fibers
  • Reticular fibers
• Collagen fibers


  Most abundant fibers, 2-10 um in diameter, have tensile strength greater than steel, flexible but inelastic, acidophilic, colorless to white in fresh tissue
• Collagen fiber formation


  1. Fibroblast synthesis

  2. Procollagen

  3. Tropocollagen

  4. Microfibrils

  5. Macrofibrils

  6. Collagen fibers
• Elastic fibers


  1 um in diameter, yellow color in fresh tissue, made up of elastin, H&E refractile pinkish-yellow lines, orcein stain blue to black, lesser tensile strength, highly insoluble protein
• Forms of elastic fibers

  • Fibrillar form
  • Non-fibrillar form