1. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings C h a p t e r 4 The Tissue Level of Organization PowerPoint® Lecture Slides prepared by Jason LaPres Lone Star College - North Harris Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

2. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Four Types of Tissues  Tissues are collections of cells and cell products that perform specific, limited functions  Types of tissue  Epithelial tissue  Covers exposed surfaces  Lines internal passageways  Forms glands

3. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Four Types of Tissues  Types of Tissue (cont’d)  Connective tissue  Fills internal spaces  Supports other tissues  Transports materials  Stores energy  Muscle tissue  Specialized for contraction  Skeletal muscle, heart muscle, and walls of hollow organs  Neural tissue  Carries electrical signals from one part of the body to another

4. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Epithelia  Layers of cells covering internal or external surfaces  Glands  Structures that produce secretions

5. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Characteristics of Epithelia  Cellularity (cell junctions)  Polarity (apical and basal surfaces)  Attachment (basal lamina)  Avascularity  Regeneration

6. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues Figure 4–1 The Polarity of Epithelial Cells.

7. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Functions of Epithelial Tissue  Provide physical protection  Control permeability  Provide sensation  Produce specialized secretions (glandular epithelium)

8. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Specializations of Epithelial Cells  Move fluids over the epithelium (protection)  Move fluids through the epithelium (permeability)  Produce secretions (protection and messengers)  Free Surface and Attached Surface  Polarity  Apical surfaces: –microvilli increase absorption or secretion –cilia (ciliated epithelium) move fluid  Basolateral surfaces

9. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Maintaining the Integrity of Epithelia  Intercellular connections  Attachment to basal lamina  Epithelial maintenance and repair

10. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Intercellular Connections  Support and communication  CAMs (cell adhesion molecules): –transmembrane proteins  Intercellular cement: –proteoglycans  Hyaluronan (hyaluronic acid): –glycosaminoglycans

11. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Intercellular Connections  Cell junctions  Form bonds with other cells or extracellular material: –occluding (tight) junctions –gap junctions –macula adherens (desmosomes) Intercellular Connections

12. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Cell Junctions  Occluding (Tight) junctions—between two plasma membranes  Adhesion belt attaches to terminal web  Prevents passage of water and solutes  Isolates wastes in the lumen  Gap junctions—allow rapid communication  Held together by channel proteins (junctional proteins, connexons)  Allow ions to pass  Coordinate contractions in heart muscle

13. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Cell Junctions  Macula adherens (Desmosomes)  CAMs, dense areas, and intercellular cement  Spot desmosomes –tie cells together –allow bending and twisting  Hemidesmosomes –attach cells to the basal lamina

14. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Attachment to the Basal Lamina  Clear layer (Lamina lucida)  Thin layer  Secreted by epithelia  Barrier to proteins  Dense layer (Lamina densa)  Thick fibers  Produced by connective tissue  Strength and filtration

15. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues Figure 4–2 Intercellular Connections

16. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues Figure 4–2 Intercellular Connections

17. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues Figure 4–2 Intercellular Connections

18. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues Figure 4–2 Intercellular Connections

19. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Epithelial Tissues  Epithelial Maintenance and Repair  Epithelia are replaced by division of germinative cells (stem cells)  Near basal lamina

20. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Singular epithelium; plural epithelia  Classes of Epithelia  Based on shape  Squamous epithelia: thin and flat  Cuboidal epithelia: square shaped  Columnar epithelia: tall, slender rectangles  Based on layers  Simple epithelium: single layer of cells  Stratified epithelium: several layers of cells

21. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia

22. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia

23. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Squamous Epithelia  Simple squamous epithelium  Absorption and diffusion  Mesothelium  Lines body cavities  Endothelium  Lines heart and blood vessels

24. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–3 Squamous Epithelia.

25. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Squamous Epithelia  Stratified squamous epithelium  Protects against attacks  Keratin protein adds strength and water resistance

26. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–3 Squamous Epithelia.

27. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Cuboidal Epithelia  Simple cuboidal epithelium  Secretion and absorption  Stratified cuboidal epithelia  Sweat ducts and mammary ducts

28. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–4 Cuboidal Epithelia.

29. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–4 Cuboidal Epithelia.

30. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Transitional Epithelium  Tolerates repeated cycles of stretching and recoiling and returns to its previous shape without damage  Appearance changes as stretching occurs  Situated in regions of the urinary system (e.g. urinary bladder)

31. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–4 Cuboidal Epithelia.

32. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Columnar Epithelia  Simple columnar epithelium  Absorption and secretion  Pseudostratified columnar epithelium  Cilia movement  Stratified columnar epithelium  Protection

33. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–5 Columnar Epithelia.

34. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–5 Columnar Epithelia.

35. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–5 Columnar Epithelia.

36. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Glandular Epithelia  Endocrine glands  Release hormones: –into interstitial fluid –no ducts  Exocrine glands  Produce secretions: –onto epithelial surfaces –through ducts Mechanisms of Glandular Secretion

37. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Modes of Secretion in Glandular Epithelia  Merocrine secretion  Is produced in Golgi apparatus  Is released by vesicles (exocytosis)  For example, sweat glands  Apocrine secretion  Is produced in Golgi apparatus  Is released by shedding cytoplasm  For example, mammary gland  Holocrine secretion  Is released by cells bursting, killing gland cells  Gland cells replaced by stem cells  For example, sebaceous gland

38. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–6 Modes of Glandular Secretion.

39. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–6 Modes of Glandular Secretion.

40. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–6 Modes of Glandular Secretion.

41. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–6 Modes of Glandular Secretion.

42. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Glandular Epithelia  Types of secretions  Serous glands: –watery secretions  Mucous glands: –secrete mucins  Mixed exocrine glands: –both serous and mucous

43. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Glandular Epithelia  Gland structure  Unicellular glands –Mucous (goblet) cells are the only unicellular exocrine glands: »scattered among epithelia »for example, in intestinal lining

44. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia  Glandular Epithelia  Gland structure  Multicellular glands: –structure of the duct: »simple (undivided) »compound (divided) – shape of secretory portion of the gland: »tubular (tube shaped) »alveolar or acinar (blind pockets) –relationship between ducts and glandular areas: »branched (several secretory areas sharing one duct)

45. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–7 A Structural Classification of Exocrine Glands.

46. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Classification of Epithelia Figure 4–7 A Structural Classification of Exocrine Glands.

47. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connect epithelium to the rest of the body (basal lamina)  Provide structure (bone)  Store energy (fat)  Transport materials (blood)  Have no contact with environment

48. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Characteristics of Connective Tissues  Specialized cells  Solid extracellular protein fibers  Fluid extracellular ground substance  The extracellular components of connective tissues (fibers and ground substance) make up the matrix  Majority of tissue volume  Determines specialized function

49. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Classification of Connective Tissues  Connective tissue proper  Connect and protect  Fluid connective tissues  Transport  Supportive connective tissues  Structural strength

50. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Categories of Connective Tissue Proper  Loose connective tissue  More ground substance, less fibers  For example, fat (adipose tissue)  Dense connective tissue  More fibers, less ground substance  For example, tendons

51. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Fibroblasts  Fibrocytes  Macrophages  Adipocytes  Mesenchymal cells  Melanocytes  Mast cells  Lymphocytes  Microphages Nine Cell Types of Connective Tissue Proper

52. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Proper Cells  Fibroblasts  The most abundant cell type: –found in all connective tissue proper –secrete proteins and hyaluronan (cellular cement)  Fibrocytes  The second most abundant cell type: –found in all connective tissue proper –maintain the fibers of connective tissue proper

53. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Proper Cells  Macrophages  Large, amoeba-like cells of the immune system: –eat pathogens and damaged cells –fixed macrophages stay in tissue –free macrophages migrate  Adipocytes  Fat cells: –each cell stores a single, large fat droplet  Mesenchymal Cells  Stem cells that respond to injury or infection: –differentiate into fibroblasts, macrophages, etc.

54. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Proper Cells  Melanocytes  Synthesize and store the brown pigment melanin  Mast Cells  Stimulate inflammation after injury or infection: –release histamine and heparin  Basophils are leukocytes (white blood cells) that also contain histamine and heparin

55. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Proper Cells  Lymphocytes  Specialized immune cells in lymphoid (lymphatic) system: –For example, lymphocytes may develop into plasma cells (plasmocytes) that produce antibodies  Microphages  Phagocytic blood cells: –respond to signals from macrophages and mast cells –For example, neutrophils and eosinophils

56. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Fibers  Collagen fibers  Most common fibers in connective tissue proper  Long, straight, and unbranched  Strong and flexible  Resist force in one direction  For example, tendons and ligaments

57. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Fibers  Reticular fibers  Network of interwoven fibers (stroma)  Strong and flexible  Resist force in many directions  Stabilize functional cells (parenchyma) and structures  For example, sheaths around organs

58. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Connective Tissue Fibers  Elastic fibers  Contain elastin  Branched and wavy  Return to original length after stretching  For example, elastic ligaments of vertebrae

59. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Ground Substance  Is clear, colorless, and viscous  Fills spaces between cells and slows pathogen movement

60. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–8 The Cells and Fibers of Connective Tissue Proper.

61. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–8 The Cells and Fibers of Connective Tissue Proper.

62. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Embryonic Connective Tissues  Are not found in adults  Mesenchyme (embryonic stem cells)  The first connective tissue in embryos  Mucous connective tissue  Loose embryonic connective tissue

63. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–9 Connective Tissues in Embryos.

64. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues [INSERT FIG. 4.9b] Figure 4–9 Connective Tissues in Embryos.

65. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Loose Connective Tissues  The packing materials of the body  Three types in adults  Areolar  Adipose  Reticular

66. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Areolar Tissue  Least specialized  Open framework  Viscous ground substance  Elastic fibers  Holds blood vessels and capillary beds  For example, under skin (subcutaneous layer)

67. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Adipose Tissue  Contains many adipocytes (fat cells)  Types of adipose tissue  White fat: –most common –stores fat –absorbs shocks –slows heat loss (insulation)  Brown fat: –more vascularized –adipocytes have many mitochondria –when stimulated by nervous system, fat break down accelerates, releasing energy –absorbs energy from surrounding tissues

68. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Adipose Tissue  Adipose cells  Adipocytes in adults do not divide: –expand to store fat –shrink as fats are released  Mesenchymal cells divide and differentiate: –to produce more fat cells –when more storage is needed

69. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Reticular Tissue  Provides support  Complex, three-dimensional network  Supportive fibers (stroma)  Support functional cells (parenchyma)  Reticular organs  Spleen, liver, lymph nodes, and bone marrow

70. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–10 Adipose and Reticular Tissues.

71. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–10 Adipose and Reticular Tissues.

72. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Dense Connective Tissues  Connective tissues proper, tightly packed with high numbers of collagen or elastic fibers  Dense regular connective tissue  Dense irregular connective tissue  Elastic tissue

73. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Dense Regular Connective Tissue  Tightly packed, parallel collagen fibers  Tendons attach muscles to bones  Ligaments connect bone to bone and stabilize organs  Aponeuroses attach in sheets to large, flat muscles

74. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–11 Dense Connective Tissues.

75. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Dense Irregular Connective Tissue  Interwoven networks of collagen fibers  Layered in skin  Around cartilages (perichondrium)  Around bones (periosteum)  Form capsules around some organs ( e.g., liver, kidneys)

76. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–11 Dense Connective Tissues.

77. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Elastic Tissue  Made of elastic fibers  For example, elastic ligaments of spinal vertebrae

78. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–11 Dense Connective Tissues.

79. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Fluid Connective Tissues  Blood and lymph  Watery matrix of dissolved proteins  Carry specific cell types (formed elements)  Formed elements of blood –red blood cells (erythrocytes) –white blood cells (leukocytes) –platelets

80. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Fluid Elements of Fluid Connective Tissues  Extracellular  Plasma  Interstitial fluid  Lymph

81. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues Figure 4–12 Formed Elements of the Blood.

82. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Lymph  Extracellular fluid  Collected from interstitial space  Monitored by immune system  Transported by lymphoid (lymphatic) system  Returned to venous system

83. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Connective Tissues  Fluid Tissue Transport Systems  Cardiovascular system (blood)  Arteries  Capillaries  Veins  Lymphoid (lymphatic) system (lymph)  Lymphatic vessels

84. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues  Support soft tissues and body weight  Cartilage  Gel-type ground substance  For shock absorption and protection  Bone  Calcified (made rigid by calcium salts, minerals)  For weight support

85. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues  Cartilage Matrix  Proteoglycans derived from chondroitin sulfates  Ground substance proteins  Chondrocytes (cartilage cells) surrounded by lacunae (chambers)

86. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues  Cartilage Structure  No blood vessels:  Chondrocytes produce antiangiogenesis factor  Perichondrium:  Outer, fibrous layer (for strength)  Inner, cellular layer (for growth and maintenance)

87. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–13 The Growth of Cartilage.

88. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–13 The Growth of Cartilage.

89. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues  Types of Cartilage  Hyaline cartilage  Stiff, flexible support  Reduces friction between bones  Found in synovial joints, rib tips, sternum, and trachea  Elastic cartilage  Supportive but bends easily  Found in external ear and epiglottis  Fibrous cartilage (fibrocartilage)  Limits movement  Prevents bone-to-bone contact  Pads knee joints  Found between pubic bones and intervertebral discs

90. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–14 The Types of Cartilage.

91. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–14 The Types of Cartilage.

92. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–14 The Types of Cartilage.

93. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues  Bone or osseous tissue  Strong (calcified: calcium salt deposits)  Resists shattering (flexible collagen fibers)  Bone cells or osteocytes  Arranged around central canals within matrix  Small channels through matrix (canaliculi) access blood supply  Periosteum  Covers bone surfaces  Fibrous layer  Cellular layer

94. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues Figure 4–15 Bone.

95. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Supportive Connective Tissues

96. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Membranes  Are physical barriers  That line or cover portions of the body  Consist of  An epithelium  Supported by connective tissues

97. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Four Types of Membranes  Mucous membranes  Serous membranes  Cutaneous membrane  Synovial membranes

98. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Mucous membranes (mucosae)  Line passageways that have external connections  In digestive, respiratory, urinary, and reproductive tracts  Epithelial surfaces must be moist  To reduce friction  To facilitate absorption and excretion  Lamina propria  Is areolar tissue

99. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Serous Membranes  Line cavities not open to the outside  Are thin but strong  Have fluid transudate to reduce friction  Have a parietal portion covering the cavity  Have a visceral portion (serosa) covering the organs

100. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Three Serous Membranes  Pleura:  Lines pleural cavities  Covers lungs  Peritoneum:  Lines peritoneal cavity  Covers abdominal organs  Pericardium:  Lines pericardial cavity  Covers heart

101. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes Figure 4–16 Membranes.

102. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes  Cutaneous membrane  Is skin, surface of the body  Thick, waterproof, and dry  Synovial membranes  Line moving, articulating joint cavities  Produce synovial fluid (lubricant)  Protect the ends of bones  Lack a true epithelium

103. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Membranes Figure 4–16 Membranes.

104. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Internal Framework of the Body  Connective tissues  Provide strength and stability  Maintain positions of internal organs  Provide routes for blood vessels, lymphatic vessels, and nerves  Fasciae  Singular form is fascia  The body’s framework of connective tissue  Layers and wrappings that support or surround organs

105. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Internal Framework of the Body  Three Types of Fasciae  Superficial fascia  Deep fascia  Subserous fascia

106. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Internal Framework of the Body Figure 4–17 The Fasciae.

107. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue  Specialized for contraction  Produces all body movement  Three types of muscle tissue  Skeletal muscle  Large body muscles responsible for movement  Cardiac muscle  Found only in the heart  Smooth muscle  Found in walls of hollow, contracting organs (blood vessels; urinary bladder; respiratory, digestive, and reproductive tracts)

108. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue  Classification of Muscle Cells  Striated (muscle cells with a banded appearance)  Nonstriated (not banded; smooth)  Muscle cells can have a single nucleus  Muscle cells can be multinucleate  Muscle cells can be controlled voluntarily (consciously)  Muscle cells can be controlled involuntarily (automatically)

109. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue  Skeletal Muscle Cells  Are long and thin  Are usually called muscle fibers  Do not divide  New fibers are produced by stem cells (myosatellite cells)

110. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue Figure 4–18 Muscle Tissue.

111. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue  Cardiac muscle cells  Are called cardiocytes  Form branching networks connected at intercalated discs  Are regulated by pacemaker cells  Smooth muscle cells  Are small and tapered  Can divide and regenerate

112. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue Figure 4–18 Muscle Tissue.

113. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Muscle Tissue Figure 4–18 Muscle Tissue.

114. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Neural Tissue  Also called nervous or nerve tissue  Specialized for conducting electrical impulses  Rapidly senses internal or external environment  Processes information and controls responses

115. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Neural Tissue  Neural tissue is concentrated in the central nervous system  Brain  Spinal cord

116. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Neural Tissue  Two Kinds of Neural Cells  Neurons  Nerve cells  Perform electrical communication  Neuroglia  Supporting cells  Repair and supply nutrients to neurons

117. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Neural Tissue  Cell Parts of a Neuron  Cell body  Contains the nucleus and nucleolus  Dendrites  Short branches extending from the cell body  Receive incoming signals  Axon (nerve fiber)  Long, thin extension of the cell body  Carries outgoing electrical signals to their destination

118. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Neural Tissue Figure 4–19 Neural Tissue.

119. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  Tissues respond to injuries to maintain homeostasis  Cells restore homeostasis with two processes  Inflammation  Regeneration

120. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  Inflammation = inflammatory response  The tissue’s first response to injury  Signs and symptoms of the inflammatory response include  Swelling  Redness  Heat  Pain

121. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  Inflammatory Response  Can be triggered by  Trauma (physical injury)  Infection (the presence of harmful pathogens)

122. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  The Process of Inflammation  Damaged cells release chemical signals into the surrounding interstitial fluid  Prostaglandins  Proteins  Potassium ions  As cells break down  Lysosomes release enzymes  That destroy the injured cell  And attack surrounding tissues  Tissue destruction is called necrosis

123. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  The Process of Inflammation  Necrotic tissues and cellular debris (pus) accumulate in the wound  Abscess: –pus trapped in an enclosed area  Injury stimulates mast cells to release  Histamine  Heparin  Prostaglandins

124. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  The Process of Inflammation  Dilation of blood vessels  Increases blood circulation in the area  Causes warmth and redness  Brings more nutrients and oxygen to the area  Removes wastes  Plasma diffuses into the area  Causing swelling and pain  Phagocytic white blood cells  Clean up the area

125. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair Figure 4–20 An Introduction to Inflammation.

126. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  Regeneration  When the injury or infection is cleaned up  Healing (regeneration) begins

127. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tissue Injuries and Repair  The Process of Regeneration  Fibrocytes move into necrotic area  Lay down collagen fibers  To bind the area together (scar tissue)  New cells migrate into area  Or are produced by mesenchymal stem cells  Not all tissues can regenerate  Epithelia and connective tissues regenerate well  Cardiac cells and neurons do not regenerate (or regenerate poorly)

128. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Aging and Tissue  Aging and Tissue Structure  Speed and efficiency of tissue repair decreases with age, due to  Slower rate of energy consumption (metabolism)  Hormonal alterations  Reduced physical activity

129. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Aging and Tissue  Effects of Aging  Chemical and structural tissue changes  Thinning epithelia and connective tissues  Increased bruising and bone brittleness  Joint pain and broken bones  Cardiovascular disease  Mental deterioration

130. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Aging and Tissue  Aging and Cancer Incidence  Cancer rates increase with age  1 in 4 people in the United States develops cancer  Cancer is the #2 cause of death in the United States  Environmental chemicals and cigarette smoke cause cancer