1. Tissues Tissue Histology The Four Primary Tissue Types Epithelial
Connective
Muscular
Nervous

2. Epithelial Tissue Epithelium / -a = cell layer (barrier)
Covering or lining—inside and out
Permeability control
Sensation
Glands = secretory structure

3. Structural Characteristics of Epithelia
apical
Cellularity
Polarity
Avascular
Innervated
Regenerative ability
basal BM

4. Polarity of Epithelial Cells

5. Classification of Epithelia
The function of the epithelium determines which type.
Typically classified according to
1. Number of cell layers Simple vs. Stratified
2. Shape of cell Squamous, cuboidal, columnar
Special features
Cilia, villi, goblet cells
End with epithelium to complete the naming

6. Arrangements
Simple
Stratified
Pseudostratified
Transitional

7. Shapes
Squamous
Cuboidal
Columnar

8. Special Features
Cilia
Goblet Cells
Microvilli
Villi

9. Simple Squamous Epithelium
1 cell thick
Friction reduction
Diffusion/filtration
Locations:
Lining of ventral body cavities, e.g. peritoneum
Lining of blood vessels (endothelium)
Alveoli

10. Lung

11. Simple Cuboidal Epithelium
Function:
Secretion
Absorption
Location:
Lining of ducts
Glands (salivary, pancreas, thyroid)
Kidney tubules

12. Thyroid Follicle

13. Simple Columnar Epithelium
Functions
Secretion
Absorption
Locations
GI tract
Excretory ducts
Reproductive tract
Special Features

14. Pseudostratified Ciliated Columnar Epithelium
Function: Mucociliary Blanket
Mixture of cell heights  nuclei located at various distances from surface.
Locations Respiratory tract except for lungs Male reproductive ducts

16. Stratified Squamous Epithelium
Multiple layers = better protection
Keratinized vs. non-keratinized
Location? Where we need protection!
Skin surface
Entrances/exits of body

18. Stratified cuboidal and columnar:  rare, found in glands and ducts
Sweat gland

19. Transitional Epithelium
Function
Extreme expansion & recoil
Layered appearance due to overcrowding.
Location
Bladder, ureters

20. stretched

22. Location in the Body

23. Connective Tissue: Supports, protects, binds tissues
Structural characteristics:
Specialized cells
Extracellular matrix
Protein fibers
Ground substance
Mostly highly vascular

24. Functions Structural framework Transport Support and protection
Energy storage

25. Classification of Connective Tissue

26. Connective Tissue Proper
Types:
Areolar Dense regular Reticular
Adipose Dense irregular
Types of Fibers:
Collagen Elastic Reticular
Defense:
Macrophages Plasma Cells Mast Cells Other WBC

27. Membranes = Combination of Epithelia & C.T.
Mucous membranes
Lining of cavities that communicate with exterior
Serous membranes
Lining of sealed, internal cavities
Cutaneous membranes
Skin
Need to know membranes
Parietal vs. visceral