Lab 4 Bone and Axial Skeleton J R

Lab 4 Bone and Axial Skeleton J. R. Schiller, Ph. D. , G. R. Pitts, Ph. D. , & Amy L. Thompson, Ph. D.

Lab 4 Activities 1. Describe functions of skeleton 2. Learn histology of bone and cartilage using microslides, figures, and osteon models 3. Learn general anatomy of a long bone 4. Classify bones by shape/origin 5. Define each of the various bone markings 6. 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

Spongy Bone

Histology of Compact Bone • Structural unit = osteon

The Osteon osteon Slide 19 Central canal

Ground Bone Slide 19 lamellae ( = central canals)

Hyaline Cartilage 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 Axial Skeleton (blue)

Lateral Aspect of the Skull

Medial Aspects of the Skull

Inferior Aspect of the Skull

Inferior Aspect of Cranium

The Vertebral Column Note the Double Curvature of the Spine. It is an Adaptation for Upright Posture.

Examine the Vertebrae from All Angles

Posterolateral View of Articulated Vertebrae Much of the Rotation of the Head Occurs at the Joint Between the Atlas (C 1) and Dens of the Axis (C 2).

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

The Bony Thorax

End Lab 4 Presentation.