Skip to main content
Back

Bones & Skeletal Tissue - Anatomy & Physiology

Control buttons has been changed to "navigation" mode.
1/20

Terms in this set (20)

  • What is bone composed of?

    Bone is a living connective tissue that responds to its environment.
  • What are the major functions of bone?
    • Support the body
    • Protect soft organs
    • Produce blood cells
    • Store fat and minerals
    • Act as levers for muscles
  • How are bones categorized?
    Bones are categorized based on their shape: Long, Short, Flat, Irregular, and Sesamoid bones.
  • Characteristics of long bones
    Shaped like a rod with a shaft and expanded ends. Examples include arm and leg bones.
  • Characteristics of flat bones
    Thin, flat, and slightly curved bones such as the sternum, ribs, and cranial bones.
  • What is the difference between compact and spongy bone?
    Compact bone is dense with no visible spaces, optimized for strength and hardness. Spongy bone looks like scaffolding, contains trabeculae, reduces weight, and spaces are filled with marrow.
  • What is the periosteum?
    A connective tissue covering the outer surface of bone with two layers: fibrous (dense irregular connective tissue) and osteogenic (bone stem cells).
  • What is the endosteum?
    A thin connective tissue lining the internal bone surfaces, similar in composition to the osteogenic layer of the periosteum.
  • What are the two types of bone marrow?
    • Red marrow: site of hematopoiesis, found in spongy bone of adults and all bone marrow in children.
    • Yellow marrow: fat storage, found in medullary cavity, can revert to red marrow.
  • What is the function of the nutrient foramen?
    A small hole in the diaphysis allowing blood vessels and nerves to enter and supply the bone.
  • What is the structure of a long bone?
    Consists of epiphysis (ends), diaphysis (shaft), metaphysis (growth area), medullary cavity (marrow-filled space), and articular cartilage covering the epiphysis.
  • What is the epiphyseal plate?
    A line of hyaline cartilage in the metaphysis that allows bone growth until it ossifies into the epiphyseal line.
  • What are the two main components of bone matrix?
    • Inorganic matrix: hydroxyapatite crystals providing hardness.
    • Organic matrix (osteoid): collagen fibers and ground substance providing flexibility and tensile strength.
  • What are the four types of bone cells?
    • Osteoprogenitor cells: bone stem cells
    • Osteoblasts: build bone by secreting matrix
    • Osteocytes: mature cells maintaining matrix
    • Osteoclasts: break down bone for remodeling
  • Role of osteoblasts
    Produce new bone matrix by secreting collagen fibers and enzymes; active in bone growth and repair.
  • Role of osteocytes
    Maintain bone matrix, monitor bone stress, and regulate calcium homeostasis; reside in lacunae and communicate via canaliculi.
  • Role of osteoclasts
    Multinucleate cells that dissolve bone matrix by secreting acid and enzymes; essential for bone remodeling and calcium regulation.
  • What is an osteon?
    The structural unit of compact bone, consisting of a central canal, concentric lamellae, and lacunae containing osteocytes.
  • What are trabeculae?
    Small struts or beams in spongy bone that contain lamellae, osteocytes, and canaliculi; align with lines of stress.
  • How does the arrangement of collagen fibers affect bone strength?
    Alternating collagen fiber directions in lamellae provide strength in multiple directions; uniform orientation would weaken bone against multi-directional stress.