Histology Notes

1. Pseudo stratified
• False stratified appearance
• All cells resting on a basement membrane
but not all of them reach the surface
( columnar & basal cell)
• Nuclei are at variable level
• No nuclei in the apical 1/3 of the
cytoplasm
• Associated with cilia & goblet cells

3. Transitional epithelium
• Specialized epithelium
• Urothelium
• It can stretch greatly without losing its
integrity
• Undistended
• Distended

4. UNDISTENDED L/M
• 5 -6 LAYERS
• BASAL LOW COLUMNAR CELLS
• MIDDLE LAYER POLYHEDRAL & FLASK
SHAPE CELLS
• UPPER LAYER LARGE DOME SHAPE CELLS
bulge into lumen
dark pink line
mono/binucleate
indentations on under surface

6. Distended L/M
• 2-3 layer
• Basal low cuboidal
• Surface cells approach a squamous form

7. CHARACTERISTICS
• UNILAMINR
• MITOTIC ACTIVITY
• IMPERMEABLE
• STRETCHING

8. ELECTRON MICROSCPE
• All cells reach basal lamina through
slender processes
• Outer lipid layer Thick integral proteins
– Plaques Uroplakin
– Interplaque areas hinges
• Concentration of microfilament
– Internalization of membrane vesicle
• Desmosomes between adjacent cells

9. CHARACTERISTICS
• UNILAMINR MITOTIC ACTIVITY
– All cells reach basal lamina through slender
processes
• IMPERMEABLE
– Thicker outer layer of cell membrane
– desmosomes
• Ability to change surface area
– Mucosal folding
– Dome cells

11. GLANDULAR EPITHELIUM
• UNICELLULAR
• MULTICELLULAR
ENDOCRINE aggregated cells form
anastomosing cordswith interspersed capillaries
EXOCRINE
Architectural classification
mode of secretion
Type of secretion

13. Architectural

14. • Simple
tubular
straight large intestine
coiled----sweat glands
branched---cardiac end of stomach
alveolar
straight----urethra
branched-----pyloric part of stomach
• Compound
tubular-----Brunner gland
alveolar----excretory part
tubuloalveolar---submandibular

15. MODE OF SECRETION
• APOCRINE
apical part of cell is lost with secretion
modified sweat gland
• MEROCRINE
no part of cytoplasm is lost e.g. sweat
gland
• HOLOCRINE
whole of the cell is lost e.g. sebaceous
gland

17. TYPE OF SECRETION
SEROUS & MUCOUS
• Bluish purple • Pink
• Nucleus round basal • Flat perpiheral
• Cell out line not clear
• Lumen indistinct • Clear
• Basal basophilia
• Distinct
• No basal basophilia