The human skeleton consists of 206 bones, not counting the teeth. The bone is formed by a living tissue that forms the human skeleton next to the cartilage. Numerous functions that are detailed in the following article.
1. Key Features
Bones. The human skeleton consists of 206 bones, not counting the teeth. The bone is formed by a living tissue that forms the human skeleton next to the cartilage. Bone tissue has three basic components: mineral, organic matrix and bone cells.
Bone provides shape and support the body, protect internal organs against trauma, provides locomotion and acts as a storage place of minerals, especially calcium and phosphorus, which in turn can be released to maintain fluid balance body. It also provides bone marrow is essential for the development and storage of blood cells.
The human skeleton consists of 206 bones, not counting the teeth: 80 axial bones which include the bones of the head, face, hyoid, auditory, trunk, ribs and sternum, and 126 appendicular bones, including those of arms, shoulders, wrists, hands, legs, hips, ankles and feet.
There are two types of bone:
- Cortical or compact. It forms the outer layer and hardest bones, but most are in the diaphyseal (middle part) of long bones. Accounts for 80% of bone mass. Provides protection, support and resists the efforts that occur in the movements.
- Trabecular or spongy. Forms the major part of the vertebral body, the epiphyses (ends) of long bones and is present elsewhere. It consists of a network called lamellae arranged in trabeculae, within each trabecula cells are directly receiving nutrients from the blood flowing through the marrow cavities. It is the most active metabolic skeleton.
2. Components of the bone
- Matrix Organic
Also called osteoid, represents 25% by weight and 38% of adult bone volume. Most of the organic matrix is collagen (94%), the other party, or ground substance consists carbohidratoproteína extracellular fluid and complex. Osteocalcin is the second most abundant protein in bone after collagen is thought to influence bone mineralization, joining in part the mineral component of bone, hydroxyapatite.
- Or inorganic bone matrix
The mineral component is mainly composed of calcium and magnesium cations and phosphate anion in the form of hydroxyapatite. The hardness of the bone due to calcium salts, which form a fundamental part of its structure.
- Bone cells
· Osteoprogenitor and osteogenic: stem cells, the only division capable of daughter cells which are transformed into osteoblasts.
· Osteoblasts: synthesize collagen fibers and represent the substance of bone. Their task is to form bone tissue.
· Osteocytes: osteoblasts are already incorporated into the calcified bone matrix and are responsible for keeping alive the bone tissue.
· Osteoclasts: are the cells responsible for the resorption and removal of unwanted bone tissue, essential for development, growth, maintenance and normal repair of bone.
3. Bone formation
The bone is formed by active tissue that is formed and destroyed continuously, ie plots of old bone are destroyed and replaced by new bone.
To promote new bone formation (bone metabolism), requires an adequate intake of nutrients and minerals like calcium and vitamin D, but not only affects this aspect, since the bone metabolism is regulated by intricate interactions between the genetic potential the individual, the environment and, of course, nutritional factors.
One can speak of three training processes
- Modeling
At this stage the bone acquires and maintains its shape. Is associated with the growth in childhood and adolescence.
- Repair
Response to the invoice.
- Remodeled
Continuous cycle of formation and destruction that occurs throughout life.
During childhood and adolescence produces the highest growth and maturation of the skeleton, with bone mineralization that is consolidated at the end of puberty, when you reach peak bone mass.
The quality of bone obtained at that time is essential to prevent further risk because, thereafter, is maintained during part of adulthood and decreases in old age.
