What could be simpler and more understandable in the human body than the mouth? It is not hidden somewhere inside, it is easy to see it in the mirror and even feel it with your fingers (of course, clean). In principle, there’s nothing even worth considering: the oral cavity - it is the cavity. A hole, in other words. Meanwhile, it is a full-fledged and important organ of the digestive system, which has far from such a simple structure as it might seem, and performs a number of functions. After all, by mouth we not only eat and speak.
Do you think you have enough fingers to list all the organs in your mouth? Even if you do not take each tooth separately, your fingers will be typed more than two hands. Do not believe? Think for yourself: lips, teeth, gums, cheeks, palate, tongue, tongue, salivary glands, tonsils, the bottom of the cavity and isthmus of the pharynx. They did not expect? But this is precisely the structure of the oral cavity, and each of its organs is intended for something, even tonsils, which in many people are removed with inflammation "as unnecessary." By the way, only palatine tonsils are removed, they are tonsils, and there are also trumpet, lingual and pharyngeal tonsils, less familiar to the "general public". All of them are accumulations of lymphoid tissue and perform hematopoietic and protective functions.
If with lips, cheeks, teeth and gums everything is more or less clear, then it is worth looking at other organs more closely. Take, for example, a language that occupies a central position in all senses of the word in the oral cavity . This is a muscular organ, the fibers of which are located in different directions, so the tongue is so mobile. Performing various movements, it allows you to form numerous sounds, helps to chew and push chewed food into the throat, and on its surface there are many receptors that allow a person to distinguish tastes.
From above, the oral cavity is limited by the sky, which separates the nasal cavity and nasopharynx from it. In the anterior two-thirds, it is firm, has a bone base, and in a third it is soft, formed by muscles. In the front of it, you can feel for the tongue several transverse rollers. They are called palatine alveoli and are the rudiments of organs well developed in animals that help them chew food. The sky ends with a soft tongue blocking the entrance to the nasopharynx at the time of swallowing.
But below the oral cavity is not so interesting; perhaps the only thing that can be distinguished here is the lingual tonsil, located under the very root of the tongue. This is already an organ of the immune system that is involved in the disinfection of food.
The salivary glands deserve special attention. The oral cavity even includes several groups of such glands: multiple small ones - buccal, palatine and lingual, and paired large - parotid, submandibular and sublingual. Their purpose is clear from the name: they produce a special secret - saliva. Its quantity and composition strongly depends on the properties of the food consumed, and you yourself know that, for example, it “drives the saliva” from a lemon. The sublingual and submaxillary glands “produce” thicker saliva, and the largest glands, the parotid glands, are more fluid. In total, up to two liters of saliva are secreted by the glands of an adult per day, and this happens reflexively, without our participation and desire. Salivation in general is an unconditioned reflex, but sometimes it can also be conditional, as a response to various olfactory, visual and other irritants. When we speak at the sight of delicious food, “drooling” is not just a figure of speech, but just an illustration of a conditioned salivary reflex .
What is saliva for? It contains enzymes that serve to pre-process the food that enters the body. Oral enzymes break down carbohydrates to glucose, and its bactericidal substance lysozyme disinfects food.