the epithelial tissue department of histology and embryology
TRANSCRIPT
The epithelial Tissue
Department of Histology and Embryology
Epithelial TissuesEpithelial Tissues
• • Classification of Epithelia
①①Cell ShapeCell Shape
• • Classification of Epithelia①①Cell ShapesCell Shapes
②②Cell LayerCell Layer
StratifiedStratified
SimpleSimple
Contents:Contents: 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.
1.Simple squamous epithelium( surface view)
Material: frog mesentery
Method: silver nitrate stain( Spread slide)
Showpiece: Mesothelium
surface view
cell Irregular polygons
Membrane and extrocellular substance
Mesothelium
Nuclei are not stained,appears oval or rounded shape
The light brown granularcytoplasm
Vascular Vascular endotheliumendothelium
Simple squamous epithelium( lateral view )
Material: Stomach----
Method: H&E
Slide NO. 25
Mesothelium
Cells are flat shaped oblate nuclei
2.Simple cuboidal epithelium
Material: thyroid gland
Method: H&E
Slide NO. 35
Low power:Follicle: many big and small follicles. The
wall is consisted of simple cuboidal epi.Colliod
High power:
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
3. simple columnar epithelium
Material: human intestine
Method: H&E
Slide NO. 1
Low power:
The outline of the villi is a line of the simple columnar epithelium
1
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
Simple columnal epi.
4. pseudostratified ciliated columnar epi.
Material: Human trachea
Method: H&E
Slide NO. 3
Low power:
The inner surface of the wall is a line of the pseudostratified ciliated columnar epi.
High power:
1.Cilia2.Columnar cell 3. Goblet cell. 4. Spindle cell5.cone cell6.Basement membrane
cilia
Basement membrane
Pseudostratified ciliated columnarPseudostratified ciliated columnar epitheliumepithelium
1
2
3
4
5. Stratified squamous epithelium
Material: human esophagus
Method: H&E
Slide NO. 2
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
High power:
1.squamous cell
2.polygonal cell
3.basal cell1
23
surface
intermediate
basal
Slide NO. 33
Transitional epithelium
Material: Human urinary bladder
Method: H&E
1.epithelium
1
1
Low magnification:
The epithelium consists of many cell layers .
Middle Magnification :
Think of which functional condition does this specimen belong to ?
2
Middle cells layer
Deep cells layer
Surface cells
domeshaped cells.
Cytoplasm
Nucleolus
Cell
Goblet cell
Striated border
simple columnar epithelium
H&E stain 400 ×
The drawingThe drawing
QUESTIONSQUESTIONS What are the general features of epithelial tissue?1) contain more cells and less extracellular ground
substance2) Polarisaton: ---free outer surface: face the surface of the body or the
lumen of an organ or gland ---basal surface: face underlying connective tissue3) Avascularity, but innervation: ---no blood vessels ---rich in nerve terminals4) Having functions of protection,secretion, absorptionand sensory reception