Skeletal System and Joints (Components of the Typical Long Bone…
Skeletal System and Joints
Components of the Typical Long Bone
: Also known as the shaft, forms the long axis of the long. Between the proximal and distal epiphyses of the long bone.
: The proximal and distal ends of the long bone.
: The joint surface of each epiphysis is covered with a thin layer of Hyaline Cartilage called the Articular Cartilage.
: Membraneous connective tissue that covers the entire outer surface of each bone except on the ends of the epiphyses, which are covered by Articular Cartilage. Secured to the underlying bone by perforating collagen fiber bundles.
: Superficial part of the bone, which covers all bone surface. Deep to the periosteum, structurally it is columns of Osteons.
: Inside of all of our bones. Lines the cavity of long bones, and the ends of long bones. Composed of Trabeculae, which are covered in Endosteum.
: Whereas the Periosteum covers the outer surface of the bone, the internal bone surfaces are covered by the much thinner membraneous connective tissue Endosteum.
: The interior of all bones is mostly spongy bone, the very center of the Diaphysis of long bones has no bone tissue at all and is called the Medullary Cavity, or Marrow cavity. In adults this cavity is filled with yellow bone marrow. The spaces between the trabeculae of spongy bone are also filled with marrow.
Nutrient Blood Vessels
: Unlike cartilage, bones are vascularized. arteries and veins run throughout the bone.
Osteogenic Stem Cells
: Cells that differentiate into Osteoblasts. Found in the Periosteum and Endosteum.
: Create the bone extracellular matrix. Begins to harden with the addition of minerals.
: Maintains bone health.
: Found in the periosteum, and endosteum. Multinucleate, formed from several leukocytes. Have Microvilli, which secrete enzymes made by the osteoclasts. Enzymes breakdown bone tissue which is resorbed by the cells. Similar to a phagocyte. Can also liberate phophorus and calcium to release into the bloodstream.
Also known as Articulation, where two or more bones connect.
: Very short interconnecting fibers.
Skull only, no movement.
: Dense Regular Connective Tissue. Little to no movement. Distaltibiofibular joint.
: where teeth meet the mandible and maxillae . Peridontal ligaments. Little movement.
: Soft Spots. Membrane between cranial bones before ossification.
: Joined by Cartilage.
: Made with cartilage. Immoveable. Hyaline Cartilage. Epiphyseal Plate. Connects first rib and manubrium.
: Slightly moveable. Located between pubic bones and intervertebral joints. Hyaline and Fibrocartilage.
Structural Components of a Typical Synovial Joint
: Ends of opposing bones are covered by articular cartilage composed of Hyaline Cartilage.
: Outer layer- Dense Irregular Connective Tissue continuous with the Periosteum. Inner Layer- Areolar Connective Tissue continuous with Synovial Membrane.
: Secretes Synovial fluid which lubricates and fills the joint cavity, and also provides nourishment for the articular cartilage.
: Cushions and deepens the joint, which allows the knee joint to fit better. Composed of Fibrocartilage.
: Contains extra cartilage which divides the joint, allowing extra movement.
: A fibrous sac filled with synovial fluid that rolls to allow movement. Located between skin and bone, muscle and bone, ligament and bone, and tendon and bone.
: Specialty bursa that wraps around tendons, which allows greater lubrication. Located in various areas, including wrists and ankles.
: Viscous liquid inside joint cavities. Resembles raw egg whites.