Due in Lab 1. Skeletal System 33-34 2. Skeletal System 26 3. PreLab 6 Due next week in lab - Scientific America Article Select one article to read and complete article summary Cell Defenses and the Sunshine Vitamin (Summary in Case Study 19-20) Skin Deep (Summary in Case Study 21-22) Sex and the Secret Nerve (Instructor website) The Naked Truth (Instructor website)
The Skeletal System Introduction
Vertebral column Skull Thoracic cage (ribs and sternum) Sacrum Cranium Facial bones Clavicle Scapula Sternum Rib Humerus Vertebra Radius Ulna Carpals Phalanges Metacarpals Femur Patella Tibia Fibula (a) Anterior view Tarsals Metatarsals Phalanges
Functions 1. Support For the body and soft organs 2. Protection For brain, spinal cord and vital organs 3. Movement Levers for muscle action 4. Mineral reservoir Calcium and phosphorus 5. Hematopoiesis Marrow cavities
Bone Osseous tissue Hydroxyapatite (85%) Calcium carbonate (10%) Inorganic minerals Magnesium, sodium, fluoride Organic material Collagen Chondroitin sulfate
Bone consists of multiple tissues Endosteum A single bone may be considered an organ Yellow bone marrow Compact bone Periosteum Perforating (Sharpey s) fibers Nutrient arteries (c) Figure 6.3c
Articular cartilage Proximal epiphysis Diaphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) (b) Compact bone Bones are organs comprised of more than just osseous tissue Distal epiphysis (a) Figure 6.3a-b
Bone Classification Figure 6.2
General Bone Features Long bone anatomy (Humerus) Diaphysis Epiphysis Metaphysis Epiphyseal growth plate or line Articular cartilage Periosteum Medullary cavity Endosteum
Articular cartilage Proximal epiphysis Diaphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) (b) Compact bone Anatomy of a long bone Distal epiphysis (a) Figure 6.3a-b
Outer layer of periosteum = dense irregular fibrous sheath Endosteum Yellow bone marrow Compact bone Periosteum Perforating (Sharpey s) fibers Nutrient arteries (c) Figure 6.3c
Articular cartilage Proximal epiphysis Diaphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) (b) Compact bone Epiphyseal line is a remnant of the epiphyseal plate Distal epiphysis (a)
Bone Histology Components Cells Fibers Ground substance
Bone Histology Cells Osteogenic (osteoprogenitor) cells Stem cells in periosteum and endosteum osteoblasts Osteoblasts Bone forming cells
(a) Osteogenic cell (b) Osteoblast Stem cell Matrix-synthesizing cell responsible for bone growth Figure 6.4a-b
Bone Histology Cells Osteocytes Mature bone cells Maintain bone matrix Osteoclasts Break down (resorb) bone matrix Related to macrophages
(c) Osteocyte (d) Osteoclast Mature bone cell that maintains the bone matrix Bone-resorbing cell Figure 6.4c-d
Spongy bone (diploë) Compact bone Compact bone covers all spongy bone and the shafts of long bones Trabeculae Figure 6.5
Bone Histology Primary bone types Compact Spongy
Articular cartilage Proximal epiphysis Diaphysis Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) (b) Compact bone Distal epiphysis (a) Figure 6.3a-b
Compact bone Spongy bone Central (Haversian) canal Osteon (Haversian system) Circumferential lamellae Perforating (Volkmann s) canal Endosteum lining bony canals and covering trabeculae (a) Lamellae Perforating (Sharpey s) fibers Periosteal blood vessel Periosteum Nerve Vein Artery Canaliculi Osteocyte in a lacuna (b) Lamellae Central canal Lacunae (c) Interstitial lamellae Lacuna (with osteocyte) Figure 6.7a-c
Structures in the central canal Artery with capillaries Vein Nerve fiber Lamellae Collagen fibers run in different directions Twisting force Figure 6.6
Nerve Vein Artery Canaliculus Osteocyte in a lacuna Lamellae Central canal Lacunae (b) Figure 6.3b
Spongy bone (diploë) Compact bone Trabeculae Figure 6.5
Bone Histology Bone marrow Location Medullary cavity and spaces between trabeculae
Bone Histology Bone marrow Types Red Red blood cells Hematopoiesis Yellow Replaces red with age Fat storage Gelatinous Mostly water and protein
Skeletal System 17 Label the following Proximal epiphysis Distal epiphysis Epiphyseal line Articular cartilage Spongy bone Compact bone Medullary canal Periosteum Endosteum Diaphysis Nutrient artery Marrow Perforating (Sharpey s) fibers Turn in
Skeletal System 19 Table 6.1
Skeletal System 19 Table 6.1
Table 6.1