BIOL 121 Chp 6: The Skeletal System: Bone Tissue

  • 1,736 views
Uploaded on

This is a lecture presentation for my BIOL 121 Anatomy and Physiology I students on Chapter 6: The Skeletal System: Bone Tissue (Principles of Anatomy and Physiology, 14th Ed. by Tortora and …

This is a lecture presentation for my BIOL 121 Anatomy and Physiology I students on Chapter 6: The Skeletal System: Bone Tissue (Principles of Anatomy and Physiology, 14th Ed. by Tortora and Derrickson).

Rob Swatski, Associate Professor of Biology, Harrisburg Area Community College - York Campus, York, PA. Email: rjswatsk@hacc.edu

Please visit my website for more anatomy and biology learning resources: http://robswatski.virb.com/

More in: Education , Technology
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,736
On Slideshare
0
From Embeds
0
Number of Embeds
4

Actions

Shares
Downloads
123
Comments
0
Likes
2

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. 1   The  Skeletal   System:  Bone   Tissue   BIOL  121:  A&P  I   Chapter  6 Rob  Swatski   Associate  Professor  of  Biology   HACC  –  York  Campus  Textbook images - Copyright © 2014 John Wiley & Sons, Inc. All rights reserved.
  • 2. 2  
  • 3. 3   Skeletal  System  Tissues   Bone   Car)lage   Dense  CT   Epithelium   Adipose   Nervous  
  • 4. 4  
  • 5. 5   FuncLons  of  Bone   Supports   body   Protects   so?  )ssues   Muscle   aAachment   site  
  • 6. 6   FuncLons  of  Bone,  cont.   Mineral   storage  &   homeostasis   Produces   blood  cells  in   red  bone   marrow   (hemopoiesis)   Energy   storage  in   yellow  bone   marrow  
  • 7. 7  
  • 8. 8   Bone   Marrow  
  • 9. 9  
  • 10. 10   Anatomy  of   a  Long  Bone  
  • 11. 11   Anatomy  of  a   Long  Bone   Diaphysis   Epiphysis   Metaphysis   Epiphyseal   plate   ArLcular   carLlage  
  • 12. (b) Partially sectioned humerus Medullary cavity in diaphysis Compact bone Spongy bone Epiphyseal line Proximal epiphysis Metaphysis
  • 13. 13   Anatomy  of  a  Long   Bone,  cont.   Medullary   (Marrow)   cavity   Endosteum   Periosteum   Fibrous  layer   Osteogenic   layer  
  • 14. 14  
  • 15. 15  
  • 16. 16   Histology  of  Bone   Tissue   Compact   bone   Spongy   bone   Specialized   bone  cells   Extracellular   matrix  
  • 17. 17  
  • 18. 18   Matrix   15%  water,  30%   collagen,  55%   mineral  salts   Calcium  phosphate   (hydroxyapa)te),   calcium  carbonate,   K,  Mg       Collagen  fiber   skeleton     =  tensile  strength   CalcificaLon   (MineralizaLon)     =  hardness  
  • 19. 19  
  • 20. 20   4  Types  of   Bone  Cells   Osteogenic   cells   Osteoblasts   Osteocytes   Osteoclasts  
  • 21. 21   Osteogenic   Cells   =  Osteoprogenitor   cells   Undifferen)ated   Periosteum  &   endosteum   Develop  into   osteoblasts  
  • 22. 22   Osteoblasts   Bone-­‐building   cells   Do  not  divide   Form  bone   matrix  &  secrete   collagen  fibers   Develop  into   osteocytes  
  • 23. 23   Osteocytes   Mature  bone   cells   Maintain   bone  )ssue   No  longer   secrete   matrix  
  • 24. 24  
  • 25. 25   Osteoclasts   Largest  of  the   bone  cells   Originate  from   fused  monocytes   (wbc’s)   Bone  resorpLon  
  • 26. 26  
  • 27. 27   Compact   (Dense)  Bone   Solid,  hard,   external  layer   of  bone   Forms  diaphysis   of  long  bones   Resists  stresses   of  weight  &   movement   Arranged  in   units  called   osteons  
  • 28. 28   Osteons   =  Haversian   systems   Osteocytes   Abundant   vascular  )ssue:   blood  vessels  &   lympha)cs   Nervous  )ssue  
  • 29. (a)  Osteons  (haversian  systems)  in  compact  bone  and  trabeculae  in  spongy  bone   Compact bone Spongy bone Periosteum Medullary cavity Outer circumferential lamellae Interstitial lamellae Concentric lamellae Blood vessels Canaliculi Osteocyte Lacuna Periosteal vein Periosteal artery Periosteum: Outer fibrous layer Inner osteogenic layer Central canal Compact bone Spongy bone Inner circumferential lamellae Trabeculae Medullary cavity See Figure 6.3b for details Perforating canal Perforating (Sharpey’s) fibers Osteon
  • 30. 30   Osteon   Histology   Concentric  lamellae   of  matrix  around   central  canal   Osteocytes  inside   lacunae   Canaliculi   IntersLLal   lamellae  
  • 31. 31  
  • 32. 32  
  • 33. 33   Spongy   Bone   No  osteons   Consists  of   trabeculae   Supports  red   bone  marrow   Reduces  weight   Short,  flat,   irregular  bones   Epiphyses  of   long  bones  
  • 34. 34  
  • 35. 35  
  • 36. 36   Blood  Supply   of  Bone     Periosteal   arteries   Nutrient   arteries   Epiphyseal   arteries   Metaphyseal   arteries  
  • 37. 37   Bone  FormaLon   (OssificaLon)   Embryonic  CT  begins   as  mesenchyme   Template  for   ossifica)on   Intramembranous   ossificaLon   Endochondral   ossificaLon  
  • 38. 38  
  • 39. 39   Intramembranous   OssificaLon   Forms  flat  bones  of   skull  &  mandible   “Jelly  sandwich”   Mesenchyme  à   Osteogenic  cells   Ossifica)on  center   Osteoblasts  à  Matrix   (Calcifica)on)   Osteoblasts  à   Osteocytes   Osteogenic  cells  
  • 40. 40  
  • 41. 41  Osteoblasts  
  • 42. 42   Intramembranous   OssificaLon,  cont.   Calcifying  matrix  joins  to   form  trabeculae   Spongy  bone  forms   around  red  bone  marrow   Surface  mesenchyme  à   Periosteum   Superficial  spongy  bone   à  Compact  bone  
  • 43. 43  
  • 44. Flat bone of skull Mandible Blood capillary Ossification center Mesenchyme Osteoblast Collagen fiber Development of ossification center: osteoblasts secrete organic extracellular matrix 1 Osteocyte in lacuna Calcification: calcium and other mineral salts are deposited and extracellular matrix calcifies (hardens) 2 Canaliculus Osteoblast Newly calcified bone extracellular matrix Mesenchyme condenses Formation of trabeculae: extracellular matrix develops into trabeculae that fuse to form spongy bone 3 Blood vessel Spongy bone trabeculae Osteoblast Periosteum Compact bone tissue Spongy bone tissue Compact bone tissue Development of the periosteum: mesenchyme at the periphery of the bone develops into the periosteum 4
  • 45. 45   Endochondral   OssificaLon   Forms  longs  bones   Replaces  car)lage   with  bone   Six  step  process   Begins  with  forma)on   of  carLlage  model  
  • 46. 46   1.  Development   of  CarLlage   Model   Originates  from   mesenchyme   Basic  shape  and   length  of  bone   Hyaline  car)lage  &   chondroblasts   Perichondrium  
  • 47. 47   2.  Growth  of   CarLlage   Model   Chondrocytes  divide  &   matrix  forms   IntersLLal  growth   ApposiLonal  growth   Mid-­‐region  cells  burst   &  lower  pH   Destroys  chondrocytes   &  triggers  calcifica)on  
  • 48. 48   3.  Development   of  Primary   OssificaLon   Center   Perichondrium  à  Periosteum   Forms  periosteal  bone  collar   Nutrient  artery  penetrates   center  of  bone  model   Periosteal  bud  brings   osteoblasts  &  osteoclasts  to   center  
  • 49. 49  
  • 50. 50   4.  Development   of  Medullary   Cavity   Osteoblasts  deposit  matrix   over  calcified  car)lage   Form  trabeculae  of  spongy   bone   Osteoclasts  form   medullary  cavity  
  • 51. 51   5.   Development   of  Secondary   OssificaLon   Center   Blood  vessels  enter   uncalcified  epiphyses   Spongy  bone   develops  
  • 52. 52   6.  FormaLon  of   ArLcular  CarLlage   &  Epiphyseal   Plate   Epiphyseal  car)lage  does   not  ossify   Remains  as  arLcular   carLlage   Epiphyseal  (Growth)  plate   also  remains  as  car)lage   Source  of  inters))al   growth  
  • 53. Development of cartilage model: mesenchymal cells develop into chondroblasts, which form the cartilage model. 1 Proximal epiphysis Diaphysis Distal epiphysis Hyaline cartilage Perichondrium Endochondral Ossification - Overview Growth of cartilage model: growth occurs by cell division of chondrocytes. 2 Uncalcified extracellular matrix Calcified extracellular matrix Nutrient artery Periosteum Primary ossification center Spongy bone Development of primary ossification center: in this region of the diaphysis, bone tissue replaces most of the cartilage. 3
  • 54. Uncalcified extracellular matrix Development of the medullary (marrow) cavity: bone breakdown by osteoclasts forms the medullary cavity. 4 Calcified extracellular matrix Periosteum Medullary cavity Nutrient artery and vein Development of secondary ossification centers: these occur in the epiphyses of the bone. 5 Secondary ossification center Uncalcified extracellular matrix Epiphyseal artery and vein Articular cartilage Spongy bone Epiphyseal plate Formation of articular cartilage and epiphyseal plate: both structures consist of hyaline cartilage. 6 Endochondral Ossification – Overview, cont.
  • 55. (b) Twelve-week fetus. The red areas represent bones that are forming (calcified). Clear areas represent cartilage (uncalcified).
  • 56. 56   Epiphyseal   (Growth)  Plate   Chondrocytes  produce   carLlage  on  epiphyseal  side   Car)lage  replaced  by  bone   on  diaphyseal  side   Plate  closes  at  age  18-­‐25   Chondrocytes  stop  dividing   Bone  replaces  car)lage   (epiphyseal  line)  
  • 57. 57   4  Zones  of   Epiphyseal  Plate   Zone  of  ResLng   CarLlage   Zone  of  ProliferaLng   CarLlage   Zone  of  Hypertrophic   CarLlage   Zone  of  Calcified   CarLlage  
  • 58. Epiphysis (c) Lengthwise growth of bone at epiphyseal plate EPIPHYSEAL (GROWTH) PLATE: Zone of resting cartilage Zone of proliferating cartilage Zone of hypertrophic cartilage Zone of calcified cartilage Diaphysis Articular cartilage New chondrocytes are formed Old chondrocytes are replaced by bone New diaphysi s
  • 59. 59   Zone  of  ResLng   CarLlage   Anchors  growth  plate   to  bone  
  • 60. 60   Zone  of   ProliferaLng   CarLlage   Rapid  cell  division   (stacks  of  coins)  
  • 61. 61   Zone  of   Hypertrophic   CarLlage   Cells  enlarge  &   remain  in  columns  
  • 62. 62   Zone  of  Calcified   CarLlage   Thin  zone  –  mostly   dead  cells   Osteoblasts  &   osteoclasts  ac)ve  
  • 63. 63   Calcified   CarLlage  
  • 64. Ridges in periosteum create groove for periosteal blood vessel. 1 Periosteal ridges Periosteum Periosteal blood vessel Perforating canal Groove Periosteal ridges fuse, forming an endosteum-lined tunnel. 2 Endosteum Tunnel Osteoblasts in endosteum build new concentric lamellae inward toward center of tunnel, forming a new osteon. 3 Endosteum Bone grows outward as osteoblasts in periosteum build new circumferential lamellae. Osteon formation repeats as new periosteal ridges fold over blood vessels. 4 Circumferential lamellae Periosteum New osteon Central (haversian) canal
  • 65. Ridges in periosteum create groove for periosteal blood vessel. 1 Periosteal ridges Periosteum Periosteal blood vessel Perforating canal Groove
  • 66. Periosteal ridges fuse, forming an endosteum-lined tunnel. 2 Endosteum Tunnel
  • 67. Osteoblasts in endosteum build new concentric lamellae inward toward center of tunnel, forming a new osteon. 3 Endosteum
  • 68. Bone grows outward as osteoblasts in periosteum build new circumferential lamellae. Osteon formation repeats as new periosteal ridges fold over blood vessels. 4 Circumferential lamellae Periosteum New osteon Central (haversian) canal
  • 69. Medullary cavity Bone formed by osteoblasts Bone destroyed by osteoclasts Infant Child Young adult Adult (b) Macroscopic changes
  • 70. 70   Factors   AffecLng  Bone   Growth:   Nutri&on   Calcium  &  Phosphorus   Vitamin  C  à  collagen   Vitamins  K  &  B12  à   protein  synthesis  
  • 71. 71   Factors   AffecLng  Bone   Growth:   Hormones   Insulinlike  Growth   Factors  (IGFs)   Thyroid  hormone,   hGH,  insulin   Estrogen  &   testosterone  
  • 72. 72   Bone   Homeostasis   Remodeling   Osteoclasts   Osteoblasts  
  • 73. 73   OrthodonLcs  
  • 74. 74   The  Effects  of   Corsetry  
  • 75. 75   Bone   Fractures   Greens)ck   Impacted   Open   Comminuted   PoA   Colles’   Stress  
  • 76. Ulna Greenstick Radius Wrist bones
  • 77. Humerus Impacted
  • 78. Humerus Open (Compound) Radius Ulna
  • 79. Humerus Comminuted
  • 80. Tibia Pott Fibula Ankle bones
  • 81. Ulna Colles’ Radius Wrist bones
  • 82. 82   Fracture  Repair  
  • 83. Copyright © 2014 John Wiley & Sons, Inc. All Periosteum Fracture hematoma Fibrocartilaginous callus (soft) Reactive phase: formation of fracture hematoma 1 Reparative phase: fibrocartilaginous callus formation 2a Reparative phase: bony callus formation 2b Bone remodeling phase 3 New blood vessel Spongy bone trabeculae Bony (hard) callus Healed fracture
  • 84. 84   1.  Reac&ve  Phase:  FormaLon  of  fracture   hematoma  (clot)  
  • 85. 85   2.  Repara&ve  Phase:  FibrocarLlaginous     callus  formaLon  
  • 86. 86   3.  Repara&ve  Phase:  Bony  callus   formaLon  
  • 87. 87   4.  Bone  Remodeling  Phase  
  • 88. 88   Calcium   Homeostasis  &   Bone  Tissue   Skeleton  =  Calcium   reservoir   Nerve  &  muscle  fiber   func)on   Blood  clohng   cascade   Enzyme  func)on   9-­‐11  mg  Ca+2/100  ml   plasma  
  • 89. 89   Hormonal   RegulaLon  of   Ca+2   Parathyroid  Hormone   (PTH)   Calcitriol   Calcitonin  
  • 90. STIMULUS CONTROLLED CONDITION Blood calcium (Ca2+) level RECEPTORS CONTROL CENTER Parathyroid hormone gene EFFECTORS RESPONSE Increase in blood Ca2+ level Osteoclasts increase bone resorption Kidneys retain Ca2+ in blood, excrete phosphate in urine, and produce calcitriol Parathyroid gland cells Return to homeostasis when response brings blood Ca2+ level back to normal Disrupts homeostasis by decreasing Detect lowered Ca2+ concentration which increases production of cyclic AMP Input Output Gene “turned on” which increases release of PTH Osteoclasts Kidneys
  • 91. 91   How  do  they   do  this?  
  • 92. 92   Aging  &  Bone   Tissue   Demineraliza)on   Osteoporosis   Reduced  protein   synthesis   Less  collagen   Less  growth   hormones  
  • 93. 93  
  • 94. 94   Disorders  of   Bone   OssificaLon   RickeAs   Osteomalacia  
  • 95. 95  The  End