Ch. 4 Tissue: The Living Fabric

Items Students Need To Look Up Prior To Class Definition of Cells and Tissues What the 4 types of human tissues are Epithelial Tissues: general location, Cell Density, difference between apical and basal surface of cells, what avascular means, how often they do mitosis, how they are classified by number of layers and cell shape Basic Functions of Simple Epithelial Tissues: Simple Squamous, Simple Cuboidal, Simple Columnar, and Psuedostratified Ciliated Columnar Basic Functions of Stratified Epithelium– keratinized and non-keratinized, and transitional epithelium

I. Introduction *A. Cells = *B. Tissues =

Stained Tissues for Microscopy *C. Four primary types: Stained Tissues for Microscopy Fixed Cut Stained Artifacts

II. Epithelial Tissues B. Characteristics Boundaries: Glands Matrix *A. General Locations Boundaries: Glands B. Characteristics *1. Cell Density Matrix *2. Cell Polarity: Apical surface Basal surface 3. Basal Lamina & Basement membrane: 4. Connective Tissue Below Apical Surfaces Basal Surface Lab Clue: no spaces . . between cells

Stratified cell shape of top layer B. Characteristics … *5. Avascular *6. Mitosis *C. Classification of Epithelium Layers Simple: Stratified: 2. Shape of Cells Squamous Cuboidal Columnar Stratified cell shape of top layer Figure 3.17a

Classification of Epithelia … Simple or Stratified?

D. SPECIFIC TYPES 1. Simple Squamous Epithelia –. - Locations D. SPECIFIC TYPES 1. Simple Squamous Epithelia – - Locations *- Functions Alveoli of Lungs SPECIAL TYPES Endothelium – inner covering of heart, lymph, and blood vessels Mesothelium – epithelium of serous membranes Figure 3.18a

Simple Squamous Epithelium in the Kidney Glomeruli Glomeruli of Kidneys

Kidney Tubules- no microvilli 2. Simple Cuboidal Epithelia - Locations *- Functions - Special Structures - microvilli Central nucleus Microvilli

Sweat Gland– made of cuboid /columnar epithelia

3. Simple Columnar Epithelia – - Locations: - 3. Simple Columnar Epithelia – - Locations: - *Functions: - Special Structures - Goblet cells, Microvilli, and Cilia Microvilli

Simple Columnar in Small Intestine Lining (showing Microvilli & Goblet Cell) Goblet Cell w/ mucus

4. Pseudostratified Columnar Epithelia – - Locations - Structure 4. Pseudostratified Columnar Epithelia – - Locations - Structure *- Functions - Special Structures: cilia & goblet cells

Pseudostratified ciliated columnar inside trachea Goblet Cells

5. Stratified Squamous Epithelia - Types: keratinized and non-keratinized - Location *- Function - Basal Cells - Top cells Non-keratinized (Non-keratinized)

Keratinized Stratified Squamous Epithelium

6. Transitional Epithelia - Structure - Cell Shape - Locations 6. Transitional Epithelia - Structure - Cell Shape - Locations *- Functions

7. Stratified cuboidal and columnar epithelia RARE Stratified cuboidal Stratified columnar

E. Glandular Epithelium: gland = 1. Major Type of Gland Endocrine gland Exocrine gland

E. Glandular Epithelium … 2. Exocrine Gland Classification: # cells a) Number of Cells Unicellular Goblet Cells & Mucus Cells Multicellular Goblet Cell Multicellular Gland

E. Glandular Epithelium … b) Multicellular by complexity Simple Compound: c) Complexity of Secretory Portion d) Classification by what is secreted: Mucous Sweat, Oil Salivary glands E. Glandular Epithelium …

e) Modes of Secretion Merocrine Mechanism: Types/Locations Apocrine Mechanism Holocrine

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Review Question 4. Epithelium tissue with multiple layers of flat cells are known as __________________________ . If the cells attached to the basal membrane are cuboidal but the cells on the apical surface are flat, the tissue is called _________________________ .

Review Questions 5a. List 2 functions of simple squamous epithelium. 5b. List 1 function of stratified squamous epithelium.

Review Questions 1a.What are the 6 major functions of epithelial tissues? Do all epithelial tissues carry out all of these functions? 1b.What type of ET is shown here?

Review Question 2. Fully describe the gland below: endocrine or exocrine? Simple or compound? Merocrine or Holocrine?

F. Embryonic Origin of Tissues Ectoderm Mesoderm Endoderm