Lab 4 Bone and Axial Skeleton J.R. Schiller, PhD., G.R. Pitts, PhD., & 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 CompactCompact –appears very dense SpongySpongy –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 Central canal Slide 19

Ground Bone ( = central canals) lamellae Slide 19

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 (C1) and Dens of the Axis (C2).

Regional Characteristics of Cervical, Thoracic, and Lumbar Vertebrae For Blood Vessels Facets for Rib to Attach. No Facets for Rib to Attach Key Differences Among Vertebral Types: Size Of Body

The Bony Thorax

End Lab 4 Presentation.