Copyright © 2009 Pearson Education, Inc. Chapter 5- The Skeletal System  Structure of bone  Bone Development  Axial and appendicular bone  Joints- articulations  Bone diseases

Copyright © 2009 Pearson Education, Inc. Skeletal System: Made of Connective Tissue  Bone: hard inorganic matrix of calcium salts  Compact: forms shaft and ends, contains marrow space  Spongy: trabeculae  Cells: osteoblast, osteocytes, osteoclasts  Types: long, flat, irregular  Osteons/haversian system: cellular arrangement  Periosteum: CT covering

Copyright © 2009 Pearson Education, Inc. Structure of Bone Figure 5.1

Copyright © 2009 Pearson Education, Inc. Cartilage and Ligaments  Cartilage  Function: support  Types: fibrocartilage, hyaline, and elastic cartilage  Ligaments  Function: attach bone to bone

Copyright © 2009 Pearson Education, Inc. Bone Development  Prenatal: cartilage model  Fetus: some conversion to bone  Childhood: primary and secondary ossification sites formed  Adolescence: cartilage growth plate elongates

Copyright © 2009 Pearson Education, Inc. Bone Development (cont.) Figure 5.2

Copyright © 2009 Pearson Education, Inc. Animation—Bone Repair Mature Bone Remodeling and Repair  Changes in shape, size, strength  Dependent on diet, exercise, age  Bone cells regulated by hormones  Parathyroid hormone (PTH): removes calcium from bone  Calcitonin: adds calcium to bone  Repair: hematoma and callus formation PLAY

Copyright © 2009 Pearson Education, Inc. Functions of the Skeletal System  Protection: encases most internal organs  Support: allows body positions  Permits movement: muscle attachments for movement  Mineral reservoir: calcium and phosphorus

Copyright © 2009 Pearson Education, Inc. Skeletal System: Frontal View Figure 5.5 Cranium Maxilla Mandible Clavicle Sternum Ribs Humerus Vertebrae Ulna Radius Coxal bone Sacrum Femur Patella Tibia Fibula Tarsals Metatarsals Phalanges Carpals Metacarpals Phalanges Scapula Axial skeletonAppendicular skeleton

Copyright © 2009 Pearson Education, Inc. Axial Skeleton: The Skull Figure 5.6 External auditory meatus Occipital bone Temporal boneParietal bone Sphenoid bone Frontal bone Zygomatic bone Ethmoid bone Lacrimal bone Nasal bone Maxilla Mandible Occipital bone Maxilla Palatine bone Foramen magnum Vomer bone Sphenoid bone Zygomatic bone

Copyright © 2009 Pearson Education, Inc. Axial Skeleton: Vertebral Column Figure 5.7 Cervical vertebrae (7) Thoracic vertebrae (12) Lumbar vertebrae (5) Sacrum (5 fused) Coccyx (4 fused) Intervertebral disks

Copyright © 2009 Pearson Education, Inc. Axial Skeleton: Vertebral Column (cont.)  Vertebral column  Regions: cervical, thoracic, lumbar, sacral, coccygeal  Intervertebral disks: cushion vertebrae; assist in movement and flexibility  Ribs  Twelve pairs  Bottom two pair floating  Sternum: breastbone  Three bones fused together

Copyright © 2009 Pearson Education, Inc. Appendicular Skeleton  Pectoral girdle: shoulder  Clavicle and scapulas  Pelvic girdles: hip  Coxal bones, sacrum, pubic symphysis  Limbs  Arms: humerus, radius, ulna, wrist and hand bones  Legs: femur, tibia, fibula, ankle and foot bones

Copyright © 2009 Pearson Education, Inc. Joints (Articulations)  Classified by degree of movement  Fibrous joint: immovable (e.g., fontanels)  Cartilagenous joint: slightly movable, cartilage connection (e.g., backbone)  Synovial joint: freely movable

Copyright © 2009 Pearson Education, Inc. Synovial Joints Figure 5.12a

Copyright © 2009 Pearson Education, Inc. Synovial Joints (cont.)  Joint capsule: synovial membrane + hyaline cartilage  Synovial membrane secretes synovial fluid as a lubricant  Hyaline cartilage acts as a cushion

Copyright © 2009 Pearson Education, Inc. Diseases and Disorders of the Skeletal System  Sprains: stretched or torn ligaments  Bursitis and tendinitis: inflammations  Arthritis: inflammation of joints