Remodeling Cycle

| D. bone remodeling | - as the patient starts to use (or bear weight on) the bone, the bone starts to remodel along lines of maximal stress (this remodeling process requires the activity of both osteoblasts and osteoclasts

Hyaline- found in the bronchi, larynx, nose trachea Elastic- external ear, epiglottis Fibrocartilage- found in the knees and elbows 13. List the main classifications for bones. Give an example for each classification. Long bones- femur and radius Short bones- lunate bone and first cuniform Sesamoid bones- patella Flat bones- frontal bone and scapulae Irregular bones- hyoid bone and atlas bone 14. Describe the structure of a long bone. Diaphysis- shaft Epiphysis- ends of bone; contain red marrow Medullary cavity- contains yellow marrow Epiphysis plate- found between diaphysis and epiphysis; long bone growth 15. Differentiate between osteocytes, osteoclasts and osteoblasts. Osteoclast- cells which dissolve bone Osteoblast- cells which build bone by removing calcium and phosphates form the blood in the presence of the enzymes alkaline phosphates secrete by

Bone remodeling This is where the body replaces old bone with new bone. The woven bone is replaced by lamellar bone. Osteoclasts remove small bone fragments and osteoblasts deposit spongy bone, converting it to compact

One of the key elements of regulating skeletal growth is the Osteoclasts. The Osteoclasts are responsible for initiating the bone remodeling cycle. Blood vessels and nerves are able to penetrate the bone once the chondrocytes die

Longitudinal bone growth occurs at the epiphyseal plate, which is a thin layer of cartilage between the epiphyseal and metaphyseal bone at the distal ends of the long bones. Bone growth is the result of maturation, growth of chondrocytes, their production of bone matrix, and finally calcification (47). The growth plate is a complex structure consisting of different layers of cells, as shown in figure 3. The most immature cells, the stem cells, are found towards the epiphyseal end of the growth plate in the stem cell zone, or resting zone; the proliferating zone contains more mature chondrocytes and the hypertrophic zone contains the larger chondrocytes. The resting stem cells in the resting zone are recruited, whereupon proliferation and differentiation

What is the difference between FOP bones and normal bones? Bone is a living tissue and made up of cartilage. Fibrodysplasia ossificans progressiva bone appears as normal bone tissue, but it develops in the wrong places. Osteogenesis and ossification are medical terms which refer to the formation of bone. Most bones in the human body grow and heal up after a break through endochondral bone formation, which is how FOP bones grow. Cartilage forms first and then the bone will eventually take the place of cartilage.

2. What are the roles of osteoclasts in bone formation? Osteoclasts are large cells that function to reabsorb, or to digest bone tissue. They digest bone tissue from the inner sides of bones thus enlarging the inner bone cavity so that the bone does not become overly thick and heavy.

The bone mass and bone strength is decreased, due to loss of tissue. Due to the loss of bone strength and bone mass the bones are easier to break and fracture. The bone is formed on a protein base by the deposition of minerals that is particularly calcium. Out of

The skeletal system, while appearing inert at first glance, is a dynamic organ responsible for a number of vital functions in the body; including but not limited to providing protection and support to other organ systems, as well as permitting movement through collaboration with the muscular system. At the cellular level, bone provides a reservoir of growth factors and cytokines, maintains the acid-base balance and mineral homeostasis, and is the site of hematopoeisis. Like other connective tissue, bone has both a cellular and an extracellular matrix component. The matrix is made up of collagen fibers and noncollagenous proteins, with type I collagen accounting for ~90% of total protein, and the noncollagenous osteocalcin, osteopontin, and bone sialoprotein, and others making up the other 10%. In contrast with other connective tissue, the extracellular matrix of bone is mineralized physiologically, though the deposition of layers of carbonated hydroxyapatite. This mineral component, making up 50-70% of bone, provides bone 's characteristic mechanical rigidity and strength (Clarke 2008). Elasticity and flexibility are due to the organic matrix, which makes up another 20-40%, lending bone incredible resilience without compromising its strength, and another 5-10% of bone is water.

As the remodeling process that conducts by both of the cells is unstable, the bone tissues are affected too. Bones consists of two types of bones tissue which is compact bone and spongy bone. Compact bone also known as cortical bone is the hard outer layer of the bone and it is found beneath the periosteum. It provides support and protection and withstands the stress produce by weight and movement. Meanwhile, spongy bone also called as trabecular or cancellous bone is usually found at the end of the long bones. The spongy bone tissues have a honey-comb like structure. In osteoporosis, the bones tissue start to break down faster than it can regenerate. Hence, the bones tissue slowly lose their density and becomes thinner. Plus,the holes structure

Bone remodeling is required to repair old the bone and to prevent the aging effects and its consequences. This process requires balance between bone formation and bone resorption and direct communication among different bone cells. Cells of the osteoblast lineage (osteoblasts, osteocytes) and bone-resorbing cells (osteoclasts), together with their precursor

Human Bones-Remodeling and Repair Bones are constantly growing and expanding; they are undergoing replacement and remodeling. It is obvious that during childhood our bones grow, the long bones (those in the arms, legs, and back) grow at the ends of the bones, while the flat bones (like those in our skulls) have a different pattern of growth. What many people do not know is that our bones are constantly growing and changing from the time we are born until we die. The process is microscopic, constant and inconspicuous. When a bone breaks; however, the remodeling and repair process is faster and much more noticeable after a bone is broken. When a bone breaks there are a series of happenings that our body undergoes in order to repair and remodel.

As a results of osteoclast death, the remodeling site becomes free of osteoclasts (Del Fattore , Teti ,and Rucci 2008). Phase 3: osteoblast precursors proliferate and differentiate at the remodeling site and start synthesizing new collagen matrix (Wilson 2011). They also initiate matrix mineralization by releasing small matrix vehicles which include Ca and phosphate and ALP (Anderson 2003). Additionally, the osteoblasts produce different factors that are stored within the newly synthesized bone for future use and released during subsequent remodelling cycles (Kang 2012). Phase 4: As bone formation persists, osteoblasts be come entrenched more deeply into the bone and eventually become surrounded by bone and are

How optimum bone strength and BMD is maintained Bone remodeling is a five-stage process. Bone is renewed to prevent accumulation of micro-damage and maintain bone strength and BMD (Burr,

The two main age-related changes that are seen in this system pertain to the bones and soft tissues. Bone is the fundamental part