2. Tissues
Chapter 4

3. Tissues groups of cells with common role 4 basic types: Epithelial
Connective
Muscular
Nervous

4. Epithelial Tissue High capacity for cell division.
Cells close together – continuous sheets
Cover surfaces & line cavities- always a free surface =Apical surface
Basement membrane of connective tissue
No blood vessels- avascular
Have a nerve supply
High capacity for cell division.

5. Categories- Table 4.1 Simple epithelium = Stratified Epithelium=
1 layer of cells
Stratified Epithelium=
more than 1 layer of cells
Cell Shapes =
squamous, cuboidal, columnar, transitional (change shape)

6. Simple Epithelium Squamous= single layer of flat cells.
Important for filtration (kidneys) or diffusion (lungs & capillaries)
Called endothelium when lining heart, blood and lymphatic vessels
Called mesothelium when in serous membranes

7. Simple Squamous Epithelium single layer of flat cells

8. Simple Squamous Epithelium single layer of flat cells

9. Simple Squamous Epithelium single layer of flat cells

10. Simple Cuboidal Epithelium cube shaped cells, rounded nuclei

11. Simple Cuboidal Epithelium cube shaped cells, rounded nuclei

12. Simple Columnar Epithelium May be ciliated or non-ciliated

13. Simple Columnar Epithelium May be ciliated or non-ciliated

14. Simple Columnar Epithelium May be ciliated or non-ciliated

15. Simple Columnar Epithelium May be ciliated or non-ciliated

16. Pseudostratified Columnar appears stratified: nuclei at various levels

17. Pseudostratified Columnar appears stratified: nuclei at various levels

18. Stratified Squamous Epithelium
Apical layer cells are flat
Deep layers vary from cuboidal to columnar
Cells in the basal layer divide and move upward toward apical surface
Found in areas of surface wear & tear

19. Table 4.1f figure 1

20. Table 4.1f figure 2

21. Stratified Cuboidal Epithelium rare

22. Stratified Cuboidal Epithelium rare

23. Stratified Columnar Epithelium rare

24. Stratified Columnar Epithelium rare

25. Transitional Epithelium variable in appearance—cells can stretch

26. Transitional Epithelium variable in appearance—cells can stretch

27. Glandular Epithelium-Endocrine

28. Glandular Epithelium-Endocrine

29. Glandular Epithelium-Endocrine

30. Glandular Epithelium-Endocrine

31. Connective Tissue Most abundant tissue type small cells far apart
large amount of extracellular material (matrix)
Often good blood supply
Found between other tissues
Classified using matrix characteristics

32. Connective Tissue Cells vary with tissue type
Fibroblasts- present in several tissues
secrete fibers & ground substance
Macrophages- from monocytes
Engulf bacteria & cell debris by phagocytosis
Plasma cells- develop from B lymphocytes
Make antibodies

33. Connective Tissue Cells
Mast cells- near blood cells
part of reaction to injury- histamine
Adipocytes= fat cells or adipose cells
Store triglycerides (fat)

34. Extracellular Matrix Fluid, gel or solid plus protein fibers
Ground substance-between cells and fibers
Fibers- 3 types
Collagen fibers: very strong & flexible
Elastic fibers: smaller stretch and return to original length
Reticular fibers: provide support & strength
found in basement membranes & organ support

35. Figure 4.2

36. Loose Connective Tissue
Areolar
Adipose
Reticular

37. Table 4.2a figure 1

38. Table 4.2a figure 2

39. Table 4.2b figure 1

40. Table 4.2b figure 2

41. Table 4.2c figure 1

42. Table 4.2c figure 2

43. Classification Dense Connective tissue Dense regular Dense irregular
Elastic

44. Table 4.2d figure 1

45. Table 4.2d figure 2

46. Table 4.2e figure 1

47. Table 4.2e figure 2

48. Table 4.2f figure 1

49. Table 4.2f figure 2

50. Cartilage
Dense network of collagen & elastic fibers embedded in chondroitin sulfate
stronger than dense fibrous
Cells = chondrocytes
Occur singly or in groups
Found in spaces called lacunae
Surrounded by perichondrium
No blood vessels or nerves

51. Classification - Cartilage
3 types
Hyaline- fibers not easily visible
Fibrocartilage- fibers visible
Strongest type. E.g. in vertebral discs
Elastic- chondrocytes in threadlike network e.g. ear cartilage

52. Table 4.2g figure 1

53. Table 4.2g figure 2

54. Table 4.2h figure 1

55. Table 4.2h figure 2

56. Table 4.2i figure 1

57. Table 4.2i figure 2

58. Bone = Osseous Tissue
More dense matrix includes Calcium & phosphorus salts
Details in Chapter 6

59. Liquid Connective Tissue
Blood- matrix = plasma
More in chapter 14
Lymph- matrix like blood but with less protein
More in chapter 17

60. Muscular Tissue large, elongated cells contractile cells
Skeletal muscle tissue -named for location
Cardiac muscle tissue- forms wall of heart
Smooth muscle tissue –found in walls of hollow organs

61. Neural Tissue Nerve cells & neuroglia
Neurons- convert stimuli into nerve impulses and conduct them
Neuroglia –do not generate nerve impulses.
Serve supportive functions

62. Body Membranes 4 types of body (not cell) membranes
Mucous Membranes –line body cavities opening to exterior
Secrete mucus
Serous Membranes- surround moving organs
Secrete serous fluid
Synovial Membranes- line cavities of some joints.
Secrete synovial fluid

63. Tissue Repair New cells from stroma or parenchyma
Epithelial cells originate from stem cells in defined areas of tissue layer
Bone regenerates readily, cartilage poorly
Muscular tissue can replace cells but slowly
Nerve tissue is poorest at replacement although some stem cells seem to be available.
Replacement from stroma –> scar tissue & functional loss.