Cell & tissue nursing

Cell & tissue nursing

1. Cell & Tissue Rishi Pokhrel MBBS, MD Maj Assistant prof of Anatomy

2. Classification Somatic and germ cells Somatic cells are present in body structure and contain 46 pairs of chromosomes. Germ cells are formed for the purpose of reproduction and they are present only in testes or ovaries. They contain 26 pairs of chromosomes. On the basis of regeneration cells can be Labile cells : cells undergoing continuous replication e.g. epithelium of skin and mucosa, uterus, secretory glands, bone marrow, blood, spleen and lymphoid tissue. Stable cells : these cells undergo very slow or infrequent replication e.g. cells of liver, kidney and pancreas, fibroblasts, smooth muscle cells etc. Permanent cells : these cells do not divide after normal growth and development e.g. neurons, skeletal and cardiac muscle cells.

3. Composition water (70-80 % ) Proteins (10-20% ) Lipids (2%) and Carbohydrates (1%). E lectrolytes like Sodium, Calcium, Chloride, Potassium, magnesium, phosphate, sulfate and bicarbonate

4. Cell organells Cell membrane

5. Organelles Cytoplasm Endoplasmic reticulum Ribosomes Mitochondria Golgi bodies Lysosomes Nucleus Centrioles

6. Nucleus

7. Cytoskeleton Cell junctions Tight junctions Gap Junctions Desmosomes

8. Tissue Epithelial tissue Connective tissue Muscular tissue Nervous tissue

9. Epithelium

10. Glands “An organ in the body that secretes particular chemical substances for use in the body or for discharge into the surroundings” Epithelial cells are major components of glands

11. Classification Duct system Endocrine Paracrine Exocrine Simple Compound Mixed

12. Means of secretion Merocrine (Eccrine) – sweat, mammary Apocrine – genitoanal glands Holocrine – Sebaceous Cells producing - Testis Classification

13. No of cells Unicellular – goblet cells Multicellular Type of secretion Mucus Serous Classification

14. Secretory component Tubular Acinar Coiled Branched Classification

15. Embryological origin Ectodermal - sweat Mesodermal – kidneys, testis Endodermal - GI Classification

16. Connective tissue “Connective tissues (CT) are a group of tissues which connects or binds other tissues in the body”

17. CHARACTERISTICS Predominantly intercellular material (matrix) Cells widely spaced Development – mesoderm, neural crest (head region) Blood vessels – few supply Classification – based on matrix, cells , fibres

18. COMPOSITION: CONNECTIVE TISSUE

19. Composition

20. CONNECTIVE TISSUE

21. CELLS OF CONNECTIVE TISSUE

22. FIBRES COLLAGEN ELASTIC RETICULAR

23. Collagen Ligament -TS Ligament - LS

24. Elastic fibers

25. Reticular fibers

26. Collagen Elastic Reticular Color Pearly white Yellow - No Largest Next > In emb CT Stain & appearance Dull pink with eosin Bright, highly refractive Not stained by H & E Protein Collagen Elastin Reticulin thickness 1-12 um 0.1-0.2 um thinnest Features Wavy, do not branch, run in bundles < wavy, branch, run singly Straight, branch & anastomose-reticulum Sites To provide strength; tendon, ligament etc. To provide elasticity; lig nuche , vocal cords, lungs, aorta To provide support; spleen, liver, lymph nodes, kidney, BM

27. GROUND SUBS Amorphous, transparent, semi-fluid gel Proteoglycans, hyaluronic acid (GAG), water Proteoglycans: chondroitin SO 4 , chondroitin 6 SO 4 , dermatan SO 4 , heparan SO 4 , heparin SO 4 , keratan SO 4

28. CLASSFICATION OF C. T. Types of cells Types of fibres Amount of ground subs Location

29. AREOLAR TISSUE

30. ADIPOSE TISSUE

31. TENDON L. S.

32. TENDON T. S.

33. Bone Definition: “ Specialized connective tissue with a solid matrix which is mineralized & adapted for giving strength , support & helping in wt. transmission”

34. Classification General microstructure Non – lamellar bone / woven bone - immature Lamellar bone – mature Compact bone Spongy spongy

35. COMPOSITION

36. Osteoprogenitor /osteogenic cells From pluripotent stromal stem cells Mesenchymal Resemble young fibroblasts In adults Deepest layer of periosteum Endosteum

37. Osteoblasts Resemble plasma cells 15 – 30 µ Roughly cuboidal Nu eccentric Cytoplasm deeply basophilic EM – typical protein secreting cell Function Synth & secretion of osteoid Mineralization of matrix

38. Osteocytes Smaller & < basophillic Major cell type Oval, 25 µ in long axis Prominent nu Cell in lacuna Canaliculi 0.25 – 0.5µ

39. Osteoclasts Large cells 20 - 100 µ Oval cells with multiple nu 15 – 20 or > Where active resorption Cells in pits – resorption bays/ lacunae of howship

40. Woven Bone / Non Lamellar Bone Most primitive form Most bone – pre natal life Post natal Repair of # Rapidly growing bone tumors (osteogenic cells) Mechanically weak

41. Lamellar Bone/ Mature Bone

42. Haversian System

43. Bone Ground Section L.S .

44. Bone Ground Section T.S.

45. Periosteum Outer covering Absent Articular surface Sesamoid bones Two layers Outer fibrous Inner cellular Sharpey ’ s fibres/ extrinsic fibres

46. Sharpey ’ s Fibres

47. Cartilage Specialized connective tissue for high resistance – tension, compression & shearing (Resilience & Elasticity) Avascular, no lymphatics, no nerve supply Low metabolic rate

48. Constituents Cells – chondrocytes, chondroblasts Located in lacunae M atrix Fibers: Collagen , elastic G round substance: hyaluronic acid, proteoglycans, glycoproteins , chondroitin SO4 Macromolecules , water & fibers bind together to give firm, flexible property

49. Perichondrium Dense CT that covers cartilage (except articular & fibrocartilage) Supplied by vessels & nerves Contains collagen fibers, fibroblasts

50. Types of Cartilage Hyaline Costal Articular Elastic Fibro cartilage

51. Hyaline Cartilage N ose , trachea, larynx Bluish white color Strong, rubbery & flexible

52. Hyaline Cartilage

53. Elastic Cartilage Similar to hyaline Fibers: collagen + elastic Found in - auricle of ear, external auditory canals, eustachian tubes, epiglottis Maintains shape, deforms but returns to shape; flexibility of organ; strengthens and supports structures.

54. Elastic Cartilage

55. Fibrocartilage No Perichondrium Collagen fibres (Type I) Densely packed bundles Feathery appearance Merge with surrounding CT Scanty Chondrocytes Small cells in lacunae form short rows between dense bundles of collagen fibres

56. Identifying features Costal cartilage Perichondrium + Ground glass appearance Cells ++ Articular cartilage Perichondrium – Ground glass appearance Cells + Elastic cartilage Perichondrium + Elastic fibers seen Cells ++ Fibrocartilage Perichondrium – Feathery appearance Cells +

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