Certainly, many ever thought about how many bones in humans.It is because of the large number of bones of people perform rather complicated manipulation of the fingers, flexion and extension of your body, and that the bones protect internal organs from outside influence.The skeleton of a newborn baby is more than three hundred bones.However, as they grow older man, some of the bones fuse together, so in the body of an adult number of bones is approximately 206-208.Strange as it sounds, but to say exactly how much bone a person is not possible.
When a person is born, his bones are soft, but with time they become harder and some of them grow together.For example, on the skull of the baby are called fontanelles - the place where there is the connective tissue, which is subsequently replaced by bone.Later on the spot fontanelle bone heals, and this place becomes subtle.About how much bone a person has, in different sources indicate different information, but we can say for sure that their more than two hundred.
Human bones on the degree of hardness is sometimes compared with the steel, but they are much easier because of its porous structure.The bone tissue formed from cells and intercellular substance, which is rich in mineral components.Outside each bone is covered with periosteum, which, in turn, is permeated by numerous blood vessels that feed bone.The structure of human bones is such that they are completely insensitive, the nerve endings are only in the periosteum.In children, the advantage of bone organic substances attached to the bones elasticity.In older people, especially the elderly, the prevalence of inorganic substances causes brittle bones.
bone structure , as well as their shape is quite different.In the human body there are flat bones, tubular and mixed and pneumatic bones.For the tubular bones is accepted to long (femur and humerus, tibia, forearm) and short (metatarsal bones, metacarpal, phalanges).Relief of bones as well as their shape is directly dependent on the method of fixing them to the muscle tissue.In case the muscle is connected with the bone tissue by means of the tendons at the junction formed ridge protuberance or appendage.If the muscle tissue goes directly to the periosteum, at the connection recess is formed.
inside the bone, the spongy material in the cells and the medullary canal, is the bone marrow.In newborns all the bones of the skeleton contains red marrow, which is protective and hematopoietic function.It is a special network of reticular fibers and cells.In adults, red marrow cells only contain spongy flat bones.In the bone marrow cavities of long bones is yellow marrow, which is represented by the degeneration of the reticular stroma with fatty inclusions.
the thickest bone in the human body is the femur.It is extremely difficult to break, but this bone fracture can lead to quite serious consequences.Near the femur artery is located, in case of damage which a person can lose a lot of blood.
How many bones in a human, say, in fact, quite difficult.Different people have a different number of bones.For example, there are some extra edge and someone there is a sixth finger.About one person out of twenty has the added edge that is interesting - the presence of excess male rib is more common than the fair sex.Some people have several additional bones, located in the arch of the foot.
