1. بسم الله الرحمن الرحيم

2. EPITHELIAL TISSUE

3. 1- Epithelial membranes (Epithelia). 2- Glands.

4. EPITHELIAL TISSUE General characteristics: 1- Have cells with little intercellular space. 2- are avascular. 3- Are separated from the underlying C.T. by the basement membrane. 4- Apical surface modifications: a- Microvilli (brush border). b- Cilia. 5- Are derived from ectoderm, endoderm or mesoderm.

5. Parameters for classification of epithelial membranes (1) The shape of most superficial cells: a- squamous (flat) b- cuboidal c- columnar

6. (2)The Number of cell layers: a- Simple b- stratified

7. (3) Function: a- Protection b- Absorption c- Secretion d- Excretion e- Transport f- Sensory reception

8. TYPES OF EPITHELIAL MEMBRANES (A) Simple Epithelium: 1- Simple squamous epithelium 2- Simple cuboidal epithelium 3- Simple columnar epithelium: a- with cilia b- without cilia 4- Pseudostratified columnar epith.: a- with cilia b- without cilia

9. TYPES OF EPITHELIAL MEMBRANES (B) Stratified epithelium: 1- Str. Squamous epith. 2- Str. Cuboidal epith. 3- Str. Columnar Epith. 4- Transitional epith.

12. MICROVILLI

13. CILIA

14. SIMPLE EPITHELIUM D. Pseudo-stratified columnar epith.

15. STRATIFIED EPITHELIUM C. Str. Cuboidal epith. D. Str. Columnar epith. XXXXXXXXXXXXXX

16. Simple squamous epithelium Endothelium

17. Simple squamous epithelium

18. Simple cuboidal epithelium

20. Simple Columnar Epithelium

21. Pseudostratified columnar epithelium

22. Non-keratinized Stratified Squamous epithelium

23. Keratinized stratified squamous epithelium

24. Transitional Epithelium

25. GLANDS

26. CLASIFICATION OF GLANDS Glands are classified according to the following parameters: (1)Presence or absence of ducts: Exocrine. Endocrine. (2) No. of cells: Unicellular: e.g. Goblet cell. Multicellular.

27. CLASIFICATION OF GLANDS (3) Nature of secretion: Serous: serous acini Mucous: mucous acini Seromucous: Seromucous acini Aqueous (watery) Fatty Waxy

28. CLASIFICATION OF GLANDS (4) Mechanism of secretion: a- Merocrine (by exocytosis) b- Apocrine c- Holocrine

29. CLASIFICATION OF EXOCRINE GLANDS (5) Branching of duct & Shape of secretory unit: - Simple - Simple branched - Compound branched - Tubular - Alveolar (acinar) - Tubuloalveolar

30. TYPES OF EXOCRINE GLANDS

31. GOBLET CELLS

35. MAJOR SALIVARY GLANDS

36. SEROUS, MUCOUS & SEROMUCOUS ACINI SEROUS DEMILUNE MYOEPITHELIAL CELLS

37. SEROUS ACINAR CELL

38. SEROUS ACINI

39. MUCOUS ACINI

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