Some childish questions can perplex any adult. So, many cannot immediately answer why the tear is salty. To understand will help knowledge of the physiological processes in the body.
Where do tears come from and why are they needed
In the area of the eyeball, under the frontal bones of the skull, there is a special amygdala. It is in it that the tear fluid is produced . From the specified gland to each eye and eyelids pass the lacrimal channels. This fluid moves along them. But this does not explain why the tear is salty.
When a person blinks, the gland is excited and begins to work. Through the channels to the eyeball comes the fluid that washes it. The tears of each person are sterile, they contain special substances - enzymes. They can destroy bacteria and thus protect the eyes from potential infections. Enzymes not only protect the eyeball, but also help get rid of foreign bodies that get into it. In addition, they moisturize it.
Reasons for salinity
As a result of studies, it was found that the biological fluid produced by the amygdala, consists of 99% pure distilled water (the formula of which is H 2 O). The remaining 1% includes various additives, one of which is sodium chloride. In tears, its content is about 0.9%.
This is the reason why the tears are salty. The answer is clear to most adults. Nevertheless, even it is difficult for them to understand why the body is structured in this way.
Less than 1% sodium chloride, which is found in tears, gives them a pronounced salty taste. In some cases, the concentration of this substance may vary.
Interesting Facts
Many, talking about why the tears are salty, say that their taste can change. It depends on the concentration of sodium chloride in this biological fluid. This, in turn, is affected by why a person is crying.
For example, it was found that in tears of joy there is a low content of various trace elements and salts. The same can be said about the tears that appear in front of young children. At the same time, the thyroid gland is at rest, and the adrenal glands, cerebral cortex and heart come into activity.
The most saline, according to endocrinologists, are tears of self-pity. In this case, the amplitude of the thyroid function increases noticeably, and the cerebral cortex also joins this process. At the same time, the adrenal glands begin to function intensely, the frequency of contractions of the heart muscle increases. With this, doctors can explain in more detail why the tear is salty.
Crying mechanism
If a person is overly upset and begins to cry, then many of his organs begin to work in a different mode. With strong physical exertion, the body is in the same state. True, in the latter case, sweat is released. By the way, he tastes like tears. In addition to sodium chloride, sweat contains magnesium, potassium, adrenaline and norepinephrine ions. All this gives the specified biological fluid a bitter taste.
The tears released during crying are concentrated in most cases. In this case, the eyes turn red, and the skin as if "burns out." Partially to explain why the tear is salty, it is possible the increased activity of the thyroid gland, adrenal glands, cerebral cortex and heart.
Biological features
In addition to tears, other fluids are in the body. All of them contain a certain amount of chlorine and sodium ions. They are found in urine, saliva, sweat, sputum, and even in the blood. This substance is necessary for the body in order to maintain the volume of fluid necessary for functioning and adhere to osmotic constancy.
For example, substances such as sodium and potassium ensure the integrity of the cells, in addition, they also take an active part in conducting nerve impulses. Sodium ions are involved in the transport of sugars and amino acids directly to cells. At the same time, a pattern is observed: the higher the concentration of sodium ions in the intercellular fluid, the better the transport of amino acids into the cells.
Also, substances such as sodium and chlorine are necessary for the digestion process, they participate in metabolic processes and create the necessary balance of the acid-base level in the cells. Therefore, underestimate the importance of sodium chloride in the body is not worth it.
Children's curiosity
Of course, telling a child about the functioning of organs and systems and the importance of the presence of sodium chloride in the body will be useful. But the baby is unlikely to understand him. Therefore, it is better to approach the story about why the tears are salty. This can be explained to the child in this way.
Ordinary water freezes in the cold, and salty remains in its liquid state for a long time. If the body was arranged differently, then the eyes would freeze in winter even with a slight cold. To say that crying on the street would be simply impossible, not even necessary. Do not forget that the eyeball is constantly washed with tears, even when a person does not cry. At the same time, the concentration of salt in tears is such that they do not freeze even at -70
o C.