1. Department of Histology and Embryology
The epithelial Tissue
Department of Histology and Embryology

2. Epithelial Tissues
• Classification of Epithelia
①Cell Shape

3. • Classification of Epithelia
①Cell Shapes
②Cell Layer
Simple
Stratified

4. Contents: Requirement:
1. Simple squamous epi. ( NO: 25)
2. Simple cuboidal epi( NO: 35)
3. Simple columnar epi. (NO: 1)
4. Pseudostratified ciliated columnar epi. (NO: 3)
5. Stratified squamous epi.( NO: 2)
6. Transitional epithelium ( NO: 33)
Requirement:
Master and recognize the main types of covering epithelia.

5. 1.Simple squamous epithelium( surface view)
Showpiece: Mesothelium
Material: frog mesentery
Method: silver nitrate stain( Spread slide)

6. surface view cell Irregular polygons
Membrane and extrocellular substance
Nuclei are not stained,
appears oval or rounded shape
The light brown granular
cytoplasm
Mesothelium

7. Vascular endothelium

8. Simple squamous epithelium( lateral view )
Slide NO. 25
Material: Stomach----
Mesothelium
Method: H&E

9. Cells are flat shaped
oblate nuclei

10. 2.Simple cuboidal epithelium
Slide NO. 35
Material: thyroid gland
Method: H&E

11. Low power:
Follicle: many big and small follicles. The wall is consisted of simple cuboidal epi.
Colliod

12. High power: The cytoplasm is stained red.
The cell is of square with a central round nucleus stained in purple blue.
The cytoplasm is stained red.
Note that the cells are as tall as they are wide

13. 3. simple columnar epithelium
Slide NO. 1
Material: human intestine
Method: H&E

14. Low power：
The outline of the villi is a line of the simple columnar epithelium 1

15. High power ： The outline of the villi is a line of the columnar cells.
The oval nucleus is close to the base of the cell, stained in blue .
The cytoplasm is stained in red.
Striated bonder
Goblet cells

16. Simple columnal epi.

17. 4. pseudostratified ciliated columnar epi.
Slide NO. 3
Material: Human trachea
Method: H&E

18. Low power：
The inner surface of the wall is a line of the pseudostratified ciliated columnar epi.

19. High power： 1.Cilia 2.Columnar cell cilia 3. Goblet cell.
4. Spindle cell
5.cone cell
6.Basement membrane
cilia
Basement membrane

20. Pseudostratified ciliated columnar epithelium1 2 3 4

21. 5. Stratified squamous epithelium
Slide NO. 2
Material: human esophagus
Method: H&E

22. Low power:
The epi. is thick which lines the inner surface of the organ. It consists of many cell layers.
1. stratified squamous epithelium 1

23. High power: surface 1 intermediate 2 3 basal 1.squamous cell
2.polygonal cell
3.basal cell
surface 1
intermediate 2 3
basal

24. Transitional epithelium
Slide NO. 33
Material: Human urinary bladder
Method: H&E

25. 1 1.epithelium Low magnification:
The epithelium consists of many cell layers .
1.epithelium 1 1

26. Middle Magnification :
Think of which functional condition does this specimen belong to ?
domeshaped cells. 2
Surface cells
Middle cells layer
Deep cells layer

27. The drawing Striated border Nucleolus Cell Cytoplasm Goblet cell
simple columnar epithelium
H&E stain 400 ×

28. QUESTIONS What are the general features of epithelial tissue?
1) contain more cells and less extracellular ground substance
2) Polarisaton:
---free outer surface: face the surface of the body or the lumen of an organ or gland
---basal surface: face underlying connective tissue
3)  Avascularity, but innervation:
---no blood vessels
---rich in nerve terminals
4) Having functions of protection,
secretion, absorption
and sensory reception