1. Lab 3: Tissue Classification, Body Membranes and Skin
Human Anatomy & Physiology Human A&P Laboratory Manual Volume 1: Third Custom Edition for APSU
Lab 3: Tissue Classification, Body Membranes and Skin

2. Lab 3 Activities
Learn the characteristics of the four main tissue types including their developmental origins
Review histology slides illustrating the variations of the four main tissue types
Review the major body membranes
Review histology slides illustrating the structure of skin 
Review skin model to reinforce understanding of the structure of skin

3. General Characteristics of Epithelial Tissues
High Cellularity: densely packed into layer(s) with little extracellular matrix
Polarity – two distinct sides
apical surface facing a space (or potential space)
basal surface supported by connective tissue
Specialized Contacts – intercellular junctions attach cells together
Innervated but avascular (no direct blood supply)
Regeneration – cells replaced at a high rate

4. Classification of Epithelial Tissues by the Shape of Cells

5. Classification of Epithelial Tissues by the Number of Layers
Simple epithelia
simple squamous
simple cuboidal
simple columnar
Stratified types named according to cell shape of the apical layer
Stratified squamous

6. Classification of Epithelial Tissues by the Number of Layers
Note: some types do not fit well into this scheme:
Pseudostratified = “falsely” stratified
Transitional > changes shape

7. Squamous epithelial (cheek) cells (scraped from stratified squamous epithelium)
Slide #3
Slide #3
© Lisa A. Caviness
© Lisa A. Caviness

8. Simple Squamous Epithelium

9. Simple Squamous Epithelium
Slide # 6
(surface view, 100X)
Slide #6
(surface view, 400X)
© Lisa A. Caviness

10. Alternative examples of simple squamous tissues
Slide # 7, kidney section, 100X
Parietal capsule of glomeruli
Sectional view, inside lining of blood vessels
© Lisa A. Caviness

11. Simple Cuboidal Epithelium
Slide # 7, kidney section, 100X
© Lisa A. Caviness

12. Alternate Example of Simple Cuboidal
Ducts of some glands
Slide # 37, thyroid section, 100X
© Lisa A. Caviness

13. Simple Columnar Epithelium
Slide # 4, uterine tube, 400X (ciliated)
© Lisa A. Caviness

14. Alternate Simple Columnar Epithelium Slides
© Lisa A. Caviness
Slide #8
Slide #8
© Lisa A. Caviness

15. Stratified Squamous Epithelium
Slide #25 plantar skin
© Lisa A. Caviness

16. Stratified Squamous Epithelium keratinized versus non-keratinized
Slide #25 plantar skin
Slide #56 esophagus
© Lisa A. Caviness
© Lisa A. Caviness

17. Stratified Columnar Epithelium

18. Transitional Epithelium
Slide #10 transitional epithelium
© Lisa A. Caviness

19. Transitional Epithelium - Bladder relaxed versus stretched
Slide #10
Slide #10

20. Pseudostratified Ciliated Columnar Epithelium

21. Pseudostratified Columnar Epithelium
Slide #11
Slide #11

22. Characteristics of Connective Tissues
Low Cellularity – widely scattered cells surrounded by extracellular matrix consisting of:
ground substance (gelatinous glycoproteins, and …)
structural fibers (collagen, elastin, reticulin protiens)
Innervated and Vascular (usually, but varies)
Usually quite regenerative

23. Major Classes of Connective Tissue

24. Embryonic Connective Tissue --Mesenchyme

25. Figure 4.7A Areolar Connective Tissue: A Prototype Connective Tissue

26. Areolar Connective Tissue

27. Areolar Connective Tissue
Slide #12
Slide #12

28. Adipose Connective Tissue
Slide 13, adipose, 100X
© Lisa A. Caviness

29. Adipose Tissue
Slide #13
Slide #13
© Lisa A. Caviness

30. Reticular Connective Tissues
Slide #14

31. Dense Regular (Fibrous) Connective Tissues
Slide #15
© Lisa A. Caviness

32. Regular Dense Fibrous Connective Tissue
Slide #15

33. Dense Irregular Connective Tissue

34. Hyaline Cartilage
Slide #17, 100X
© Lisa A. Caviness

35. Hyaline Cartilage
Slide #17, 100X
Slide #17, 400X

36. Elastic Cartilage (slide 16)
© Lisa A. Caviness

37. Elastic Cartilage
Slide #16

38. Fibro-cartilage (slide 18)

39. Fibrocartilage
Slide #18

40. Bone (Osseous Tissue) (slide 19)

41. Bone Tissue (dried)
Slide #19

42. Types of Bone Compact: appears very dense
most of the bone mass in the body
Spongy:
appears poorly organized
tiny bone struts = trabeculae

43. Blood (Vascular Tissue) (slide 20)
© Lisa A. Caviness

44. Blood Cells
Slide #20

45. Muscle Tissues Characteristics of muscle tissues
High degree of cellularity
Cells contain contractile proteins
Well vascularized

46. Muscle Tissues: Skeletal (Slide 21)
© Lisa A. Caviness

47. Skeletal Muscle
Cross-sectioned
Long-sectioned
© Lisa A. Caviness

48. Muscle Tissues: Cardiac

49. Muscle Types Slide #21 Slide #22 Skeletal muscle Cardiac muscle
attached to bones
multinucleate
voluntary
fibers are parallel and cylindrical
Cardiac muscle
most of the heart wall
single nucleus
involuntary
branched cylinders connected by intercalated discs
Slide #21
Slide #22

50. Muscle Tissues: Smooth (SLIDE 23)

51. Muscle Types Smooth muscle non-striated
walls of hollow organs: blood vessels, digestive tract, airways, bladder
involuntary
single nucleus
spindle shaped

52. Nervous Tissue Slide #24 Two basic cell types: neurons Neuroglia
transmit electrochemical signals
cell body (soma) and extensions
dendrites (highly branched) – carry incoming signal
axon (long, usually single strand) – carry outgoing signal
Neuroglia
Support neurons
Slide #24
© Lisa A. Caviness

53. Nervous Tissue (Slide 24)
© Lisa A. Caviness

54. Epithelial Membranes: Serous Membranes

55. Epithelial Membranes (Body Membranes)
A membrane is an epithelial tissue and its supporting connective tissue
Muc0us Membranes

56. Epithelial Membranes: The Cutaneous Membrane

57. The Skin

58. Hairy Skin Root Follicle Sebaceous glands Arrector pili muscles
© Lisa A. Caviness

59. Plantar Skin Epidermis Dermis Stratum corneum Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Dermis
Duct of sweat gland
© Lisa A. Caviness

60. Plantar Skin Epidermis Dermis Stratum corneum Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Dermis
© Lisa A. Caviness

61. Take Advantage of Available Histology Resources

62. End Lab 3 Presentation