1 / 30

Chapter 6: Cartilage and Bone Tissue

oakley
Télécharger la présentation

Chapter 6: Cartilage and Bone Tissue

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Chapter 6: Cartilage and Bone Tissue What does the skeletal system do for us?

    2. Cartilage Location Ear and nose Respiratory system Movable joints Costal cartilage Intervertebral disks Pubic symphysis Embryonic

    3. Cartilage Tissue Specialized CT Chondrocytes in lacunae Solid ground substance and fibers Avascular No nerves Perichondrium 60-80% water resilient

    4. Hyaline Cartilage Most abundant Locations Joints Trachea Costal cartilages Network of collagen fibers

    5. Elastic Cartilage Elastic fibers Locations External ear Epiglottis

    6. Fibrocartilage Bundles of collagen fibers in rows Locations Intervertebral disks Pubic symphysis Menisci

    7. Cartilage Growth Appositional growth From perichondrium Interstitial growth By chondrocytes within cartilage No new chondrocytes in adults and no cartilage growth

    8. Bone Functions Support body weight Protect soft organs Movement at joints Storage of Ca++ and PO4-3 Hematopoiesis

    9. Bone Shapes Long bones extremities Short bones cube-shaped, wrist & ankle Flat bones skull, sternum, scapula, ribs Irregular bones vertebrae, pelvis

    10. Compact vs. Spongy Bone Compact solid, weight-bearing, structural support Spongy marrow cavity, trabeculae, light weight

    11. Compact vs. Spongy Bone

    12. Long Bones Diaphysis shaft Epiphyses ends Epiphyseal plate/line growth region Nutrient arteries to marrow and compact bone

    13. Periosteum Fibrous layer dense irregular CT Cellular layer osteoblasts & osteoclasts Nerves Blood vessels Sharpeys fibers Attachment for tendons

    14. Endosteum Inner surface of compact bone Covers trabeculae Osteoblasts & osteoclasts

    15. Flat Bone Skull Two sheets of compact bone Diploe spongy bone

    16. Compact Bone Histology Osteon / Haversian system Structural unit of long bone Cylindrical Parallel to bone Concentric lamellae Collagen fibers in different directions Increase strength

    17. Compact Bone Histology Interstitial lamellae Circumferential lamellae Inner & outer

    18. Compact Bone Histology Central / Haversian Canals Perforating / Volkmanns Canals Endosteum Blood vessels Nerves

    19. Osteocytes Located within lacunae (cavities) in lamellae Canaliculi allow processes of osteocytes to communicate with each other & with capillaries

    20. Spongy Bone Lamellae Osteocytes Endosteum

    21. Bone Composition 35% cells, fibers (collagen), ground substance 65% mineral salts, mainly calcium phosphate precipitated around collagen fibers

    22. Bone Formation Osteogenesis development of the skeleton and growth through adolescence (~18 females, ~21 males) Osteoblasts secrete osteoid Osteoid is mineralized (calcium phosphate precipitates) Osteoblasts become osteocytes Forms woven bone (immature) Periosteum formed Mature lamellar bone formed on surfaces

    23. Intramembranous Ossification Flat bone develops from mesenchyme (undifferentiated, embryonic CT) Skull and clavicle Mesenchymal cells become osteoblasts Osteoblasts form bone

    24. Endochondral ossification Hyaline cartilage model of bone first Cartilage is replaced by bone (long bone)

    25. Bone Growth Regulated by: Growth hormone Thyroid hormone Sex hormones

    26. Abnormal Bone Growth Hyperpituitarism. Gigantism. F/19. Family photographs showed that this young woman had consistently outgrown her twin brother and was always the biggest child in the school class. She had a pituitary adenoma secreting growth hormone.

    27. Bone Remodeling Dynamic changing throughout life Osteoblasts form new bone Osteoclasts multinucleated, fused cells Secrete HCl, dissolve calcium phosphate Lysosomal enzymes digest collagen & matrix Phagocytize debris

    28. Mechanical Stress Bone tissue thickens in response to stress, e.g., exercise / weight gain Bone tissue thins in response to decreased exercise or weightlessness

    29. Osteoporosis

    30. Normal Osteoporosis

    31. Development of Skeleton

More Related