What Is Longitudinal Bone Growth?

Haematopoietic stem cells (HSC) regulate the turnover of platelets, erythrocytes and all immune cells by changing between self-renewal and differentiation to a variety of specialised cells. Osteoblasts has a major role of secretion of mineralized bone matrix proteins and cells of the osteoblast lineage regulating osteoclast differentiation. (Purton & Scadden, 2008)

Each long bone has at least two growth plates. There is one at each end. The growth plate

Endochondral Ossification. Most bones of the human skeleton are formed by endochondral ossification. During endochondral ossification, bone replaces a cartilaginous model of the bones. Chondrocytes (cartilage cells) lays down a cartilage model that is shaped like the future bones. As the cartilage model calcifies the chondrocytes die. Osteoblasts from the periosteum secrete the organic bone matrix that undergoes calcification. The result is an outer layer of compact bone called a bone collar which covers the diaphysis. Blood vessels bring osteoblasts into a region of the cartilage called the primary ossification center where they produce spongy bone. The spongy bone of the diaphysis is absorbed by Osteoclasts creating the

The bone consists of the diaphysis and epiphysis. The diaphysis is the middle part of the bone and the diaphysis are the ends of all long bones like for example the hip bone. This structure only qualifies for all typical long bones in our bodies. In this disease of osteoporosis cells of bone tissues are also involved such as osteoblasts, and osteoclasts. Osteoblasts are involved in bone forming cells and they secrete calcium and binding proteins. Osteoclasts are involved in dissolving a damage bone and is a way that the bone can be repaired.

The authors’ main argument is that the information bone turnover rates offer, which are determined by the measurement of carbon-14 content of collagen in bones, is beneficial for forensic dating and archaeological science applications. The authors also mention that the manner in which stable isotope values from collagen are interpreted can either lead to a misleading or constructive conclusion if age range is taken into consideration.

Throughout life the skeletal system is constantly changing. Bone modeling, formation and growth of bones, occurs from birth to early adulthood resulting in increase in skeletal mass and changes in skeletal form. Naturally the peak bone mass is achieved in the third decade of life, meaning the bones are at their strongest state in human development. Bone remodeling, a response to micro trauma and stress on the bone, is a dynamic process that also occurs through life. Bone is composed of collagen type 1, a protein, minerals such as calcium and phosphate and bone forming cells (osteoblasts and osteocytes) as wells as bone resorbing cells known as osteoclasts. Calcium is a main contributor of bone strength. In fact 99% of calcium is stored in bones and teeth with one percent remaining in the blood. The process of bone remodeling is activated by stressors such as weight bearing and is necessary to maintain bone mass in an adult. It’s a dynamic process in which bone resorption is always

Bones contain collagen (protein), calcium salts and other minerals. Each bone is made up of a thick outer shell known as cortical bone and a strong inner mesh of trabecular bone which looks like a honeycomb. Bone is alive and constantly changing throughout life. Old, worn out bone is broken down by cells called osteoclasts and replaced by bone building cells called osteoblasts. In childhood, osteoblasts work faster, enabling the skeleton to increase in size, density and strength. During this period of rapid bone growth, it takes the skeleton just two years to completely renew itself. In adults this process takes seven to ten years.

This process is more complex than intramembranous ossification because the hyaline cartilage must be broken down as bone formation proceeds. There are four main stages of endochondral ossification. First, perichondrium that is covering the hyaline cartilage “bone” is infiltrated with blood vessels and becomes vascularized periosteum. As a result of this change in nutrition, the underlying mesenchymal cells differentiate into osteoblasts, and the stage for ossification is set to begin. Bone collar forms around the hyaline cartilage, and osteoblasts of the new periosteum secrete osteoid against the cartilage diaphysis, encasing into a new layer of bone called the periosteal bone collar.

The process of bone development and bone growth, as well as maintaining healthy bones, is dependent upon several hormones produced in the body. The hormone Calcitriol, which is produced in the kidneys, plays a key role in the absorption of calcium and phosphate ions within the digestive system. The pituitary gland is responsible for the Growth hormone. It causes the building up of the bones, producing bone growth. The development of the hormone Thyroxine comes from the thyroid gland. Thyroxine prompts the cells metabolism and it increases the activity of bone growth. Together the Growth hormone and Thyroxine help maintain the normal growth of bones at the epiphyseal plate until the time of puberty. Upon reaching puberty there is a significant rise in the Sex hormones, estrogen and androgen.

The bone tissue in osteoblasts is constantly being reshaped which form new bone when the previous bone has been fractured, making the new bone much stronger and harder to break. They are found in the bone marrow are known as structural cells. They work in a team to build new bone and produce new bone called ‘osteoid’ which is made up of bone college and other proteins. They have the power to control the levels of calcium and mineral deposition. When they are done filling in a cavity, the cells become flat and line the surface of the bone and then are called ‘lining cells’. They respond to hormones by making special proteins that activate the osteoclasts. Once they have secreted the matric they become less reactive and maintain the matrix. When the area surrounding an osteoblast hardens, the osteoblast becomes trapped and transforms into an osteocyte which is the mature type of bone

Bones are dynamic tissues that undergo changes need to maintain bone and calcium homeostasis through a process called bone remodeling. Bone remodeling is an essential process that repairs damaged bone and maintains mineral homeostasis. This process is regulated by two main cells that perform opposite, but complementary function. Osteoblasts are the main bone forming cells that originate from mesenchymal stem cell lineage. Osteoblasts produce bone matrix which they later mineralized to form bone. During the process of bone formation, matured osteoblasts usually get trapped in the bone matrix and become osteocytes. Osteoclasts on the other hand, are the main bone resorbing cells; they resorb bone producing proteolytic enzyme and acid. In response

Bone is a living organism that is continuously regenerating its self through two stages (formation and resorption). In the resorption stage old bone is broken down then removed by cells. Then in the formation stage, new bone is built to replace the old by cells called osteoclasts. When the human body is younger more bone is produced than removed and as the body grows in age it’s the opposite also known as primary osteoporosis since it isn’t caused by other condition or long time medication.

Canine bone development and developmental bone diseases are of growing interest to researchers and consumers. In order to produce healthier canines and to reduce the incidence of diseases commonly found in canines, it is important to understand what bone development is and how it occurs, factors that influence bone development, and developmental diseases. Development can be defined as a series of changes that takes place in an animal beginning in the embryonic state and lasting until maturity. These changes lead to a more complex organizational state of the body, starting with simple cellular organization and leading to formation of body systems.

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

He initially determined the cellular sequence of bone remodelling as endothelial cells, intermediate cells, osteoblasts, osteocytes and osteoclast and that the capillary-sinusoid vessel acts as the initial framework on which this process rests. This study showed that the endothelium of the capillary system houses the cells responsible for bone formation.