1. Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Modified by S. Mendoza 8/2013 Seventh Edition Elaine N. Marieb Tissues Lecture Slides in PowerPoint by Jerry L. Cook

2. Types of Tissues

3. Histology Slide 3.41 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Cells are specialized for particular functions  Tissues  Groups of cells with similar structure and function  Extracellular Matrix  Aka: intercellular matrix, interstitial fluid  “cell glue” between cells  Histology = study of tissue

4. Body Tissues Slide 3.41 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Four primary types (functional categories)  Epithelium = protection/secretion/absorption/filtration  Connective tissue = support & structure  Nervous tissue = communication & control  Muscle = movement (internal & external)

5. EPITHELIAL TISSUES

6. Epithelium Characteristics Slide 3.43 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  High cellularity = cells fit closely together – very little EC matrix  Contains specialized contacts = tight junctions & desmosomes  Tissue layer always has one free surface (apical) that may have modification such as microvilli

7. Epithelium Characteristics Slide 3.43 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Avascular = no blood vessels within it – diffusion provides nutrients & carries waste away – lots of nerve fibers  Basement Membrane  Reinforcement & connection  Defines boundaries – cancer causes a breach in these boundaries  Regenerate easily if well nourished  Found in areas of high friction

8. Classification of Epithelium Slide 3.44b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Combination of shape & # of cells is used to name tissues  Shape of cells  Squamous – flattened  Cuboidal – cube-shaped  Columnar – column-like Figure 3.16b

9. Classification of Epithelium Slide 3.44a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Number of cell layers  Simple – one layer  Found in areas of transport  Stratified – more than one layer  High abrasion areas for protection  Secretory membranes  Named according to cell shape on apical surface Figure 3.16a

10. Apical Surface

14. Simple Epithelium Slide 3.45 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Simple squamous  Single layer of flat cells  Usually forms membranes  Lines body cavities  Lines lungs and capillaries Figure 3.17a

15. Simple Epithelium Slide 3.46 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Simple cuboidal  Single layer of cube-like cells  Common in glands and their ducts  Forms walls of kidney tubules  Covers the ovaries Figure 3.17b

16. Simple Epithelium Slide 3.47 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Simple columnar  Single layer of tall cells  Often includes goblet cells, which produce mucus  Lines digestive tract Figure 3.17c

17. Simple Epithelium Slide 3.48 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Pseudostratified  Single layer, but some cells are shorter than others  Often looks like a double cell layer  Sometimes ciliated, such as in the respiratory tract  May function in absorption or secretion Figure 3.17d

18. Stratified Epithelium Slide 3.49 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Stratified squamous  Cells at the free edge are flattened  Found as a protective covering where friction is common  Locations  Skin  Mouth  Esophagus Figure 3.17e

19. Stratified Epithelium Slide 3.50 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Stratified cuboidal  Two layers of cuboidal cells  Stratified columnar  Surface cells are columnar, cells underneath vary in size and shape  Stratified cuboidal and columnar  Rare in human body  Found mainly in ducts of large glands

20. Stratified Epithelium Slide 3.51 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Transitional epithelium  Shape of cells depends upon the amount of stretching  Lines organs of the urinary system Figure 3.17f

21. Connective tissues Support & strengthen & provide structure

22. Connective Tissue Slide 3.53 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Found everywhere in the body  Includes the most abundant and widely distributed tissues  Functions  Binds body tissues together  Supports the body  Provides protection  Insulates to maintain body temperature  Transportation of other molecules

23. Connective Tissue Characteristics Slide 3.54 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Variations in blood supply  Some tissue types are well vascularized  Some have poor blood supply or are avascular  Blood supply is necessary for healing (it brings oxygen & “spare parts”)  Cartilage vs bone: Know this answer that we discuss!!

24. Connective Tissue Characteristics Composed largely of EC matrix Important to remember: More matrix = less flexibility Compare bone to cartilage: Know the answer that we discuss!!

25. Extracellular Matrix Slide 3.55 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Two main elements  Ground substance - proteins and polysaccharide molecules that function as a molecular sieve to diffuse nutrients & other substances  Fibers – know function  Produced by the cells  Three types  Collagen fibers – tensile strength  Elastic fibers – stretch with recoil  Reticular fibers - supportive

26. Cells Prefixes Fibro Osteo Chondro Hemo(cyto) Suffixes Blast – build the tissue Cyte – maintain the tissue Clast – breakdown the cells

27. Connective Tissue Types Slide 3.56 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Bone (osseous tissue)  Composed of:  Bone cells in lacunae (cavities)  Hard matrix of calcium salts  Large numbers of collagen fibers  Used to protect and support the body Figure 3.18a

28. Connective Tissue Types Slide 3.57 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Hyaline cartilage  Most common cartilage  Composed of:  Abundant collagen fibers  Rubbery matrix  Entire fetal skeleton is hyaline cartilage Figure 3.18b

29. Connective Tissue Types Slide 3.58a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Elastic cartilage  Provides elasticity  Example: supports the external ear

30. Connective Tissue Types Slide 3.58b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Fibrocartilage  Highly compressible  Example: forms cushion-like discs between vertebrae Figure 3.18c

31. Connective Tissue Types Slide 3.59 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Dense connective tissue  Main matrix element is collagen fibers  Cells are fibroblasts  Examples  Tendon – attach muscle to bone  Ligaments – attach bone to bone Figure 3.18d

32. Loose connective tissues Are softer than dense connective tissues: have more cells and fewer fibers than any other connective tissues: 1. Areolar Tissue 2. Adipose Tissue 3. Reticular Tissue

33. Connective Tissue Types Slide 3.60 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Areolar connective tissue  Most widely distributed connective tissue  Soft, pliable tissue  Contains all fiber types  Can soak up excess fluid  When body region is inflamed, this tissue soaks up excess fluid and area becomes swollen and puffy = condition called edema. Figure 3.18e

34. EDEMA

35. Connective Tissue Types Slide 3.61 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Adipose tissue  Matrix is an areolar tissue in which fat globules predominate  Many cells contain large lipid deposits  Functions  Insulates the body  Protects some organs  Serves as a site of fuel storage Figure 3.18f

36. Connective Tissue Types Slide 3.62 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Reticular connective tissue  Delicate network of interwoven fibers  Forms stroma (internal supporting network) of lymphoid organs  Lymph nodes  Spleen  Bone marrow Figure 3.18g

37. Connective Tissue Types Slide 3.63 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Blood  Blood cells surrounded by fluid matrix  Fibers are visible during clotting  Functions as the transport vehicle for materials Figure 3.18h

38. Muscle Tissue Muscle tissue is highly vascular & highly cellular Less matrix = more flexibility More blood flow = more ATP made Elongated shape Actin & myosin – contractile myofilaments

39. Muscle Tissue Slide 3.64 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Function is to produce movement  Three types  Skeletal muscle  Cardiac muscle  Smooth muscle

40. Muscle Tissue Types Slide 3.65 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Skeletal muscle  Voluntary control  Cells attach to connective tissue  Cells are striated (striped)  Cells have more than one nucleus (multinucleate) Figure 3.19b

41. Muscle Tissue Types Slide 3.67 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Smooth muscle  Involuntary muscle  Surrounds hollow organs  Attached to other smooth muscle cells  No visible striations  One nucleus per cell (uninucleate) Figure 3.19a

42. Muscle Tissue Types Slide 3.66 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Cardiac muscle  Found only in the heart - Function is to pump blood (involuntary control)  Cells attached to other cardiac muscle cells at intercalated disks and split at the bifurcations  Cells are striated  One nucleus per cell Figure 3.19c Bifurcation

43. Nervous Tissue Consists of brain, spinal cord, nerves Carry electrical signals Neurons: generate & conduct electricity Usually nonregenerative Neuroglia: support neurons Brain tumors?

44. Tissue Repair 1. Regeneration is the replacement of destroyed tissue by proliferation of the same type of cells. 2. Fibrosis is the replacement of destroyed tissue by connective (scar) tissue. 3. The major type of tissue repair that takes place is determined by: a. The type of tissue injured b. The severity of the injury

45. Events in Tissue Repair Slide 3.70 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  1. Capillaries become very permeable  Introduce clotting proteins  Wall off injured area to stop loss of blood  2. Formation of granulation tissue: composed of new capillaries that grow into the damaged area: contains phagocytes  3. Regeneration of surface epithelium: regenerated cells move its way across the granulation tissue beneath the scab.

46. Regeneration of Tissues Slide 3.71 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tissues that regenerate easily  Epithelial tissue  Fibrous connective tissue and bone  Tissues that regenerate poorly  Skeletal muscle  Tissues that are replaced largely with scar tissue  Cardiac muscle  Nervous tissue within the brain and spinal cord

47. Developmental Aspects of Tissue Slide 3.72 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Epithelial tissue arises from all three primary germ layers (mesoderm, ectoderm, and endoderm)  Muscle and connective tissue arise from the mesoderm  Nervous tissue arises from the ectoderm  With old age there is a decrease in mass and viabililty in most tissues