Cell & tissue nursing

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

3. 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.

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

5. Cell organells
• Cell membrane

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

7. Nucleus

8. • Cytoskeleton
• Cell junctions
– Tight junctions
– Gap Junctions
– Desmosomes

9. Tissue
• Epithelial tissue
• Connective tissue
• Muscular tissue
• Nervous tissue

10. Epithelium

12. 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

13. Classification
• Duct system
– Endocrine
– Paracrine
– Exocrine
• Simple
• Compound
– Mixed

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

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

16. • Secretory component
– Tubular
– Acinar
– Coiled
– Branched
Classification

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

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

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

22. Components
Cells Matrix
Ground substance Fibers
COMPOSITION: CONNECTIVE TISSUE

23. Composition

24. Components
Cells
Fixed
Fibroblasts
Adipocytes
Persistent
mesenchymal
cells
Wandering
Macrophage
Mast cells
Plasma cells
Pigment cells
Eosinophil
Neutrophil
Matrix
Ground
substance
Proteoglycans GAG /MPS
SO4
Non SO4
Fibers
Collagen
Elastic
Reticular
CONNECTIVE TISSUE

25. CELLS OF CONNECTIVE TISSUE

26. FIBRES
• COLLAGEN
• ELASTIC
• RETICULAR

27. Collagen
Ligament -TS
Ligament - LS

28. Elastic fibers

29. Reticular fibers

30. 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

31. GROUND SUBS
• Amorphous, transparent, semi-fluid gel
• Proteoglycans, hyaluronic acid (GAG), water
• Proteoglycans: chondroitin SO4, chondroitin
6 SO4, dermatan SO4, heparan SO4, heparin
SO4, keratan SO4

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

33. Connective tissue
Adult
Ordinary
Loose
Areolar
Adipose
Reticular
Dense
Regular
Tendon
Ligament
Aponeurosis
Irregular
Subcutaneous
tissue
Specialized
Blood
Cartilage
Bone
Fetal

34. AREOLAR TISSUE

35. ADIPOSE TISSUE

36. TENDON L. S.

37. TENDON T. S.

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

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

40. Bone
Cells
Osteoprogenator cells
Osteoblasts
Osteocytes
Bone lining cells
Osteoclasts
Matrix
Ground
substance
Water
Proteoglycans
Chtn SO4, Hyal. Acid, osteocalcin, osteonection
Minerals
Ca,Ca(OH)2(PO4)6
Fibers
Collagen
COMPOSITION

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

42. 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

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

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

45. 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

46. Lamellar Bone/ Mature Bone

47. Haversian System

48. Bone Ground Section L.S.

49. Bone Ground Section T.S.

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

51. Sharpey’s Fibres

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

53. Constituents
• Cells – chondrocytes, chondroblasts
– Located in lacunae
• Matrix
– Fibers: Collagen, elastic
– Ground substance: hyaluronic
acid, proteoglycans, glycoproteins,
chondroitin SO4
• Macromolecules, water & fibers bind
together to give firm, flexible property

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

55. Types of Cartilage
• Hyaline
– Costal
– Articular
• Elastic
• Fibro cartilage

56. Hyaline Cartilage
• Nose, trachea,
larynx
• Bluish white color
• Strong, rubbery &
flexible

57. Hyaline Cartilage

60. 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.

61. Elastic Cartilage

63. 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

65. 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 +