Body homeostasis: what it is, and types of homeostatic processes
We are hungry and we eat, because our body warns us that we lack nutrients. We are thirsty and we drink, because we are in the process of dehydration and our body needs water to function well. Our pulse and respiration are accelerated by an extremely activating situation and later we calm down, because we stop being exposed to the situation that requires an energy use.
If we observe all these relationships, we can realize that in all of them we are facing a process that seeks to maintain a balance in our body .
This balance is necessary for the proper functioning of our body, with which we carry out different processes to achieve it. We are talking about body homeostasis , which we are going to talk about throughout this article.
What is body homeostasis?
We understand by body homeostasis the tendency in the body to actively and constantly seek a state of equilibrium, in such a way that the cells of our body can survive by maintaining a stable internal composition.
The maintenance of this balance is essential, since the activation or maintenance of different bodily processes require energy, which in turn requires elements to be used as fuel. If we do not dispose of them, a series of tissue damages will be produced that can lead to death . The same happens if we are not able to activate or stop some of the aforementioned bodily processes, necessary for our survival.
It is important to bear in mind that homeostasis acts on the basis of the existence of changes that can occur both within the body and from outside, using mechanisms of action that link both environments (for example, hunger makes us eat).
The feedback or negative feedback is probably the mechanism of action of homeostasis that seems to have more logic and easier to observe and understand.
This mechanism is based on the fact that given the detection of a determined level of a specific parameter that moves away from the normal values, a response is carried out that intends to return said parameter to the previous stability .
Examples of this are those provided in the introduction to this article. It must also be borne in mind that we are not talking about a search for balance that occurs only in situations where there is a lack, but also when there is an excess of something.
Another process necessary to maintain body homeostasis may, in fact, appear counterintuitive. It is about positive feedback, which is characterized by generating an increase in the amplification of disequilibrating stimuli, accelerating changes.
This process can be risky and even pose a danger to survival, but although it causes the organism to move further away than it would initially do from the balanced baseline, it has its utility: it may be necessary to perform this feedback or to move the state basal to a more optimal situation for survival or to achieve long-term return to initial situations.
Examples of this occur in the coagulation of the blood before a lesion, which becomes increasingly rapid and facilitates the arrest of a hemorrhage.
5 homeostatic processes that occur in our body
We have talked about body homeostasis as something general that may sound somewhat abstract to most readers (although several examples have been given).
But there are many aspects and functions of our body that must be regulated to allow our survival. In order to make homeostasis much more visual, let us look at five more examples (in addition to those already seen hunger, thirst, pulse and cardiorespiratory rhythm or blood coagulation) of elements that are regulated and that allow the correct functioning of our system.
1. Cellular metabolism
The cellular metabolism is undoubtedly the process that requires more regulation in order to keep us alive. And is that our cells are very delicate and need to be in a very specific environment.
It is necessary that the levels of different elements and ions of elements such as sodium , potassium or calcium, as well as the levels of intracellular fluid and extracellular fluid, be correctly regulated in order that the cells can exercise their functions and remain with life.
2. Body temperature
Another bodily mechanism that is continuously regulated is the internal temperature of the body. The proper functioning of our tissues and organs can be affected by excessive cold or heat , to the point of being able to lead to death by hypothermia or hyperthermia.
Fortunately, our body is able to maintain the temperature through a homeostatic process in which, if there is excess internal temperature, the body reacts with a decrease in physical activity, discomfort and sweating (whose objective is to reduce the temperature) or with an increase in activity, the generation of tremors, the consumption of calories , withdrawal of blood from secondary areas to direct it to vital areas and the search for heat in the case of lack of sufficient temperature.
3. Autonomic nervous system
The functioning of the autonomic nervous system is another clear example of homeostasis.
The sympathetic system allows the organism to prepare itself for the action and the fight or flight reactions in order to survive, generating a much greater energy consumption in order to carry out the necessary actions, while the parasympathetic system allows us to reduce the activity and activation in order to replenish energies or prevent an energy waste.
An example of dysregulation would occur in chronic stress problems , in which the sympathetic system would be excessively activated continuously.
4. Regulation of glucose
In this case, our body acts in such a way that it allows the sugar to be transformed into fats and stored thanks to insulin, whereas when it becomes necessary to use glucose from the body we secrete glucagon in order to transform fats into sugar. The clearest example of dysregulation occurs in diabetes .
5. Hormone regulation
Also endocrine functioning must be regulated. In fact, many of the behaviors that lead to the external generation of homeostasis, such as the sensation of hunger or thirst, sexual desire or stress, depend to different degrees on this system.
A natural and non-pathological example would be found in the female menstrual cycle , as well as in the dysregulation that menopause would initially imply.