The structure of the human ear

The ear is a very important organ that is of great importance in the life of any animal and human. The structure of the ear is closely related to the functions performed by it. It is not only a hearing aid, but also an equilibrium organ that helps you navigate in space. In humans, the normal functioning of the hearing organ is responsible for the development of speech.

Evolution and structure of the organ of hearing in animals . Before considering the peculiarities of the structure of the human ear, it makes sense to familiarize yourself with the various forms of this organ in animals. The hearing aid is designed to perceive sound waves, which is important both in communication between individuals and for survival.

In arthropods, the organs of hearing are represented by specialized sensillae, which are located on bristles, antennae or body.

The structure of the fish's ear is still quite simple, since the organ of hearing has only the inner part. It is a complex of three semicircular canals, each of which is located in a mutually perpendicular area. In special cells contain otoliths, which begin to oscillate when the sound wave passes. It is this oscillation that creates an impulse that is transmitted along the nerve to a certain area of the brain, where this information is processed.

In the representatives of amphibians appears the middle part of the ear, which is covered with a tympanic membrane. There is also one auditory ossicle - stapes. The inner ear is separated from the middle by an oval window. The cavity of the organ of hearing is connected to the oropharynx - this helps to equalize the pressure.

Of course, the structure of the ear in mammals is considered to be the most difficult. Representatives of this class, as a rule, have already formed all three departments of the hearing organ, there is an auricle, auditory ossicles, an otolith apparatus and a fully formed vestibular system.

The structure of the human ear . The human ear consists of three parts - the outer, middle and inner.

The outer ear is represented by the auricle and external auditory meatus. The auricle is a large, elastic cartilage, covered with skin. Its main function is to catch sounds. The auricle passes into the ear passage, which is lined with skin from the inside. He ends blindly on the eardrum.

The middle ear begins with the tympanic membrane, which transmits sound vibrations to the auditory ossicles - the hammer, anvil and stapes (by the way, these are the smallest bones of the human body). The sound wave causes a vibration of the bones, which is transmitted through the oval window into the cavity of the inner ear. The drum cavity is connected by a nasopharynx with the help of Eustachian tubes - thus, the pressure is equalized. It is interesting that with too much sound or increased pressure of the environment, the ears "pawn". In this case, yawning is reflexively caused - the open oral cavity reduces the probability of damage to the tympanic membrane.

The structure of the inner ear is perhaps the most difficult. It consists of a bone labyrinth in which a vestibule, a cochlea and three semicircular canals are distinguished. The snail is the most important part of the hearing organ, because it is she who perceives sound vibrations and turns them into a nervous impulse.

Inside the cochlea is a webbed labyrinth filled with a special liquid. On its walls are specific receptors, which are represented by hair cells. Each such cell perceives a lymphatic oscillation inside the labyrinth and transforms it into an electrical signal, which is then transmitted along the auditory nerve to the centers of the brain.

Three semicircular canals of the inner ear are a vestibular analyzer, which is responsible for orientation in space, movement, perception of the position of the body.

You can see that the structure of the ear of a person is quite complicated, since this body is responsible for many functions of the human body. It is also interesting that children with congenital abnormalities of the hearing aid can not communicate normally, despite the fact that the entire speech system (tongue, pharynx, vocal cords) functions normally.