The human skull is the skeleton of his head. This skeleton is divided into the facial and brain parts.
In the brain area, the skeleton of the head is close in shape to the ball. The composition of this part includes two parietal, frontal, occipital, two temporal and other bones of the human skull . In appearance, all the elements are represented by rather thick curved plates. These bones are called flat. Their task is to protect the brain from damage.
Individual bone elements in the skeleton of the head are connected using sutures. This joint is called motionless. The seam is formed by the cut edges of two adjacent elements. At the same time, the cloves of one of them include the teeth of the other.
The human skull in the brain has relatively smooth surfaces (lateral and superior). The base of the brain is covered with roughness and various protrusions. This is due to the fact that the human skull in this place is connected with muscle fibers. There are also holes in the base. Nerves and blood vessels pass through them. Approximately in the center of this part of the skeleton of the head there is a large opening (occipital), through which the brain and spinal cord join.
On the border of the lateral surfaces and the base of the skull are auditory openings (external). The lower surface of the occipital bone element has articular processes that lie on both sides of the occipital foramen. Using these processes, the human skull is connected to the spine.
The facial area of the skeleton of the head includes paired bone elements. These include maxillary, nasal, zygomatic, palatine and other bones. The mandibular bone element is not paired.
In the facial region of the skeleton of the head are the oral, nasal cavities, as well as the orbits.
The orbits are represented by a deep hollow. The eyeball lies in it, as well as its muscles, vessels and nerves.
The nasal cavity opens in front with a hole in the surface of the skeleton of the head. At the back, the nasal cavity is connected to the pharynx through two openings. The right and left half of the cavity are formed using a dividing bone septum. In each of the halves, through three bones, nasal passages are formed.
The oral cavity is separated from the nasal using the palatine bone elements and processes of the maxillary bones. The edges of the lower and upper jaws limit the mouth from the sides.
The human skull has the same parts and elements as the skeleton of the head of a mammal. However, an essential feature of the skeleton of the human head is the extremely highly developed brain part. In mammals, the front part is more developed.
The elements that form the skull of a newborn person are in a state of incomplete ossification. They are composed of connective tissue and cartilage. The occipital, frontal and other bone elements contain several components. There are no teeth at the edges of the skeleton of the head of the newborn. Thus, the connection is carried out by means of strips of connective tissue membrane, and not seams. In areas where the angles of several bone elements converge, the membranes expand, forming fontanelles.
With the development of the child, some bones join together, seams form, fontanelles overgrow. Thus, the process of ossification is gradually completed, bone growth begins.
The skeleton of the head, as well as the whole body, undergoes changes throughout the course of human life. So, from thirty years, as a rule, the process of overgrowing of joints begins. When a person reaches old age, the teeth begin to fall out and the cells in which they were located disappear.