Look Out Below: a Case Study on Bone Tissue Structure and Repair

1. A) Hemorrhage – loss of blood from the vessels via ruptured walls; aka bleeding.

B) Fracture – a break in the bone.

C) Proximal – toward the attached end of the limb or origin of the structure,

D) Diaphysis – elongated shaft of a long bone (Marieb & Hoehn, 2016).

2. Humerus – long bone

Occipital bone – flat bone

Lumbar vertebrae – irregular bone (Marieb & Hoehn, 2016).

3. Vertebrae are irregular bones which are made up of thin plates of spongy bone which is covered by compact bone. The compact bone is covered on the outside by periosteum and by endosteum on the inside (both are connective tissue membranes). These bones are also lined with fibrocartilage cartilage on their surfaces as well. Vertebral bones contain marrow but have no well-defined marrow cavity (Marieb & Hoehn, 2016).

Spongy bone is made up of a honeycomb of trabeculae, whose spaces are filled with marrow in living bones. They look disorganized by comparison to other bones and functionally, they help resists bone stress and harbor marrow. Compact bone looks solid but in fact it contains passages that allow for nerve and blood vessels to pass through. Functionally, compact bone forms the walls of the bone and bears weight and resists twisting. Periosteum is a double-layered membrane that contains a lot of nerve fibers and blood vessels and serves as an anchoring point for ligaments and tendons. Endosteum covers internal bone surfaces and canals in compact bone. Both of these membranes contain osteogenic cells that give rise into other bone cells. Fibrocartilage is comprised of chondrocytes and collagen fibers and functionally, it is highly compressible which allows it to absorbs pressure and stretch (Marieb & Hoehn, 2016).

4. The diaphysis of the humerus forms the long axis of the bone. Its composed of compact bone surrounding the medullary cavity (aka marrow cavity). Compact bone is comprised of various layers of bone tissue. The structural units of compact bone are osteons which...