A&P CHAPTER 6.docx - Chapter 6 The Skeletal System...

Info icon This preview shows pages 1–3. Sign up to view the full content.

Chapter 6: The Skeletal System Skeletal structure supports weight of body. Bones can be remodeled and reshaped to meet changing metabolic activity. Bones work with muscles to maintain body position and produce controlled and precise movements. I. Primary Functions of Skeletal System Support Storage of Minerals and Lipids: calcium salts are valuable mineral reserve that maintains normal calcium and phosphate ion concentrations in body fluids. Lipids as energy reserves are in areas filled with yellow bone marrow Blood cell Production: red, white and other blood elements are made in the red bone marrow (fills internal bone cavities) Protection Leverage: body functions as levers allowing small movements of fingertips to full body rotations II. Classification of Bones Introduction to classification 206 Bones in body Bone/Osseous tissue is supporting connective tissue that has specialized cells and a matrix of extracellular protein fibers and ground substance. Bone texture comes from calcium salt deposits in matrix Calcium phosphate = 2/3 weight of bone Collagen fibers = 1/3 weight of bone Osteocytes and other cells = 2% mass of bone Macroscopic Features of Bone Long bones: longer than wide o Have central shaft (diaphysis) that surrounds central space called marrow cavity (medullary cavity) which contains bone marrow (soft, fatty tissue) o Have expanded portions at ends called epiphyses that are covered by articular cartilages Short bones: roughly equal length and width o Ex. femur, humerus, carpal and tarsal bones Flat bones: thin and broad o Ex. parietal bone of skull, ribs, scapula Irregular bones: complex shapes o Ex. spinal column, skull bones Types of Bone Tissue Compact bone: dense; forms walls of diaphysis; thin layer of compact covers spongy bone of each epiphysis Spongy bone/trabecular bone: interlacing network of bony rods/struts separated by spaces; fills epiphyses and lines marrow cavity Periosteum: outer covering of bones consisting of outer fibrous layer and inner cellular layer o Fibers of tendons and ligament intermingle with those of the periosteum o Periosteum isolates bone from surrounding tissue, provides route for vessels and nerves and takes part in bone growth/repair Tendons: attach muscle to bones
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Ligaments: attach bone to bone Endosteum: covers spongy bone of marrow cavity and other inner surfaces; active during bone growth/repair/remodeling Microscopic Features of Bone Osteocytes in small pockets called lacunae Lacunae found between narrow sheets of calcified matrix known as lamellae Canaliculi are small channels that radiate throughout matrix and interconnect lacunae to vessels Compact Bone Osteon/Haversian System: basic functional unit of compact bone Within osteon, osteocytes are arranged around Haversian/central canals (run parallel to bone surface) Perforating/Volkmann’s canal give
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.
  • Winter '08
  • Spranger
  •  Bone texture

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern