Lab 4 Bone and Axial Skeleton J.R. Schiller, PhD., G.R. Pitts, PhD., & Amy L. Thompson, Ph.D.
Lab 4 Activities Describe functions of skeleton Learn histology of bone and cartilage using microslides, figures, and osteon models Learn general anatomy of a long bone Classify bones by shape/origin Define each of the various bone markings Identify all bones and their bone markings of the axial skeleton individually or in articulated skeletons (see list, pp. 4-9 to 4-13)
Functions of Bones • Support - framework for body • Protection of: • many internal organs including the brain, spinal cord, thoracic (heart and lungs) organs, and pelvic (reproductive) organs • Movement - muscle attachments to bones • Mineral homeostasis – storage resevoir of Ca++, PO-4 • Hemopoiesis: Site of blood cell production in red bone marrow
Bone Tissue • Compact • appears very dense • Spongy • small struts of bone = trabeculae are generally oriented with the directions of stress
Histology of Compact Bone • Structural unit is the osteon
The Osteon Slide 19 osteon Central canal
Ground Bone Slide 19 lamellae (central canals)
Hyaline Cartilage Slide 17 Slide 17 Lacunae w/chondrocytes
Elastic Cartilage Slide 16
Fibrocartilage Slide 18
Classification of Bones • Long, short, flat, and irregular (shape) • Wormian (Sutural): extra flat bones of cranium • Sesamoid: bones that form in tendon • Normal: patellae • Pathological: bone spurs
Structure of a Long Bone • Diaphysis (shaft) • medullary (marrow) cavity • red (hematopoietic) marrow in infancy • yellow (fat) marrow later • Compact bone (mostly) • nutrient foramina • Epiphyseal Plate (line) • Connects diaphysis to epiphyses • epiphyseal plate - growth plate in childhood • Epiphyseal line when growth ends • Epiphysis (“end”) • nutrient foramina • articular cartilage - hyaline cartilage • Spongy bone w/red marrow
The Vertebral Column Note the Double Curvature of the Spine. It is an Adaptation for Upright Posture.
Posterolateral View of Articulated Vertebrae Much of the Rotation of the Head Occurs at the Joint Between the Atlas (C1) and Dens of the Axis (C2).
Key Differences Among Vertebral Types: Regional Characteristics of Cervical, Thoracic, and Lumbar Vertebrae For Blood Vessels Size Of Body Facets for Rib to Attach. No Facets for Rib to Attach