The human skull. Structure

The skull consists of a set of bones of the head, firmly connected by seams between themselves. The exception is the lower jaw. In the connected bones in the head are the organs of smell, hearing and vision, as well as the brain. They are also a support for the nasal cavity and the skeleton of the oral cavity. This causes the separation of the skull into a section of the bones of the skull and a section of the bones of the face. The brain department consists of two pairs (parietal and temporal) bones, and four unpaired (frontal, wedge, occipital and latticed) bones. The irregular shape of the skull may depend on the degree of development of the chewing apparatus and the brain itself.

The occipital bone, which is part of the cranial bones, resembles a flat bowl. Its parts are limited by a large (occipital) opening, which performs the function of connecting the cranial cavity and the spinal canal. The sphenoid bone is located between the frontal and occipital bones, which are located in the base forming the skull. The structure of this bone includes a body whose upper surface is curved and has a pituitary depression, and three paired processes (large and small wings and pterygoid processes). Inside the temporal (the most complex) bone is the organ of balance and hearing. Through it also passes the nerve channel of the face, the carotid artery. In addition, there are also bone channels and a tube of the ear (bone part). The dark bone looks like a quadrangular concave bone plate with notches on the edges (except for the lower edge). On the outside of the surface of the skull there is a parietal hillock. The composition of the frontal bone includes paired orbital parts, frontal scales and a nasal part. The cranial bone is located in the deep section forming the skull. The structure of the bone includes a trellis plate with a vertical perpendicular plate that extends from it vertically down into the design of the septum of the nasal cavity.

The section of the bones of the face includes paired bones (six in total). Here there is a nasal, palatine, zygomatic, lacrimal bone, lower nose shell and upper jaw. The department also includes unpaired bones: vomer and lower jaw. The hyoid bone also forms part of the facial part that forms the skull. The structure of most bones is quite complicated. They contain channels and openings with passing nerves and blood vessels. In some separate bones there are internal sinuses (cavities, sinuses, cells) that are filled with air.

A small-sized teardrop has a crest and a lacrimal furrow. It is located on the medial orbital wall. The nose bone looks like a quadrangular plate, elongated in length. Nasal bones left and right form the basis of the bones of the nasal back. The opener is involved in the formation of the septum bone in the nasal cavity. The structure of the upper jaw includes four processes and a body consisting of four (nasal, ophthalmic, posterior (cross-section) and anterior) surfaces. In the palatine bone there are two bone plates. The size of the zygomatic bone affects the shape and width of the face. The lower jaw is the only movable element of all that forms the skull. The structure of the jaw includes the body and paired, branching at an obtuse angle from it.

The development of the bones of the head, as well as the bones of the limbs and trunk, begins with the stage of tissue connectivity. As for the parts of the skull base and their parts, their development includes cartilaginous and bone (final) stages. Bones of the roof and face pass only two stages (bone and membranous).

Senile deformations of the skull are accompanied by resorption of crests, spongy bone substance. At the same time, it becomes brittle, thereby reducing its weight. Changes in the cranial shape can be affected by mechanical influences.

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