We explain everything about bones, how they are classified, their function and structure. In addition, how many bones the human body has.
What are the bones?
Bones are a set of rigid organic structures, mineralized by the accumulation of calcium and other metals . They constitute the toughest and toughest parts of the human body and other vertebrate animals (only surpassed by tooth enamel).
The set of all the bones in the body makes up the skeletal or skeletal system, the body's physical support. In the case of vertebrates, this support is found inside the body (endoskeleton), instead of outside (exoskeleton) as in the case of arthropods and other animal edges.
In addition, within the bones is the bone marrow, which fulfills hematopoietic or blood red blood cell creation functions. That is to say that it is a set of organs with complex functions, which have adipose tissue, blood vessels and even nerves inside.
Bones are much more than simple support structures of the body, although we have the opposite idea, surely because they are the last to decompose of the human body after death.
The bones gradually solidify as the individual grows, during early childhood, and they grow along with him until he reaches his final size. Similarly, the bones can regenerate their own breaks (fractures) through a process called bone consolidation, and they are in a constant process of remodeling within the body.
See also: Human body systems
Types of bones
Depending on their shape and appearance, the bones of the human body can be classified into four categories, which are:
- Long bones . As the name implies, they have a predominant length to width and thickness, and are dense, strong bones, within which the red and yellow marrow is housed.
- Short bones These are the bones whose three dimensions (length, width and thickness) are practically the same.
- Flat bones . In these bones the length and the width predominantly over the thickness, since they usually constitute the frame of the different cavities of the body.
- Irregular bones . In this last category enter all the bones whose shape prevents them from being classified in any of the previous three.
Bones fulfill various functions in the body, which can be summarized in:
- They provide structural support to the body, retain their shape and protect the internal organs outside.
- The bone marrow produces red blood cells that carry oxygen transport in the blood.
- Together with the muscles, joints, ligaments and tendons, the bones allow voluntary movement of the body.
- Bones are an important region of storage of resources, not only calcium and phosphorus, necessary for their hardening, but also certain types of lipids and last minute use resources.
Bones are made up of three parts, called the diaphysis (central part of the body of the bone), epiphysis (ends of the long bones) and metaphysis (intermediate portion of the bone). Similarly, from the inside out, they are composed of:
- Spinal cavity The "hollow" region of the bone where the bone marrow is located, usually located in the diaphysis.
- Endostium It is a thin membrane of connective tissue that covers the inside of the medullary cavity of the long bones.
- Nutritious artery The artery that supplies blood to the bone, through its nutritional holes and then distributed through the bone through increasingly thin capillaries.
- Bone tissue . The main component of bone, consisting of bone cells (osteocytes, osteoblasts, osteoclasts and stem cells) in 2% of the tissue, and 70% of resistant extracellular substance (hydroxyapatite) secreted by them, from calcium and phosphorus, In addition to about 30% collagen.
- Perioste The fibrous and resistant connective tissue membrane that covers the bones in its outer region.
How many bones has the human body?
The bone system of the human body is composed of 206 different bones, articulated differently to the cartilage, ligaments, muscles and tendons.
Like other parts of the body, the bones can suffer injuries (fractures, trauma) or they can be the victim of diseases. The best known of these are:
- Cancer Bone marrow cancer occurs, like other tumors, by abnormal multiplication of the soft tissue cells (tumors called myelomas), or sometimes between the cells. hardened cells of its rigid part (called sarcomas). It leads to weakening of the structure and painful local numbness.
- Osteoporosis This disease consists of a chronic loss of calcium in the bones, causing them to thin and increase their fragility. It is very associated with old age and other processes of the body, so it requires a combined treatment, through calcium supplements and physical exercise.
- Paget's disease . This is the name of a congenital disease, which causes abnormal functioning of the cells that originate the bone, causing abnormal thickening and widening of the skeletal structure, which threatens the patient's health.
- Rickets A disease derived from the deficiency of vitamin D in the diet, or also of some endogenous problem that prevents the absorption of said nutrient, essential for the calcification of the bones. That is why people afflicted with this disease suffer from a progressive weakening of the bones, which thus becomes painfully fragile and brittle.
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