The Homeostasis is a complex mechanism present in living organisms which involves absorption, performance and correct process of assimilation of food and proteins entering the body. This biological action present in all living beings, represents the correct functioning of the metabolism, a structured and calibrated function between a system of hormones and brain glands, which organize this work in order to guarantee effective bodily performance.
What is homeostasis
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The concept of homeostasis is the ability of the body to perform physical-chemical and self-regulation functions that lead to maintenance and consistency in the composition and properties of the internal part of an organism. For this reason, homeostasis represents the internal balance of the human body, and it performs responses that are adjusted in order to maintain good health. An internal imbalance can be produced by different causes and the homeostatic mechanisms act immediately, through feedback and control processes, restoring balance in the body.
What is homeostasis in biology
Homeostasis in biology is a set of mechanisms or dynamic equilibrium, through which living beings manage to achieve the stability of the properties of their internal environment and the biochemical composition of tissues and cell fluids, in order to stay alive, being physiology its main basis.
Homeostasis in living beings
Homeostasis occurs in all organisms, but it has been studied more closely in the human species and in other higher mammals. In these complex animals, homeostasis operates in isolated and integrated cells. For example: body fluids, tissues and organs. Since constant conditions within the tissue are maintained, each cell is subject to smaller variations in its own external environment. There is a constant exchange of moleculesbetween the blood and the extracellular fluid that bathes each cell. The stable composition of the blood is what makes it possible to maintain the invariance of the extracellular fluid, the constant mixing of the extracellular fluid, protects each cell from the changes that occur in the external environment.
An example of homeostasis is, if a person takes a hot bath, in this case the temperature of the cells in the liver, heart, intestine and pancreas is not altered.
Homeostasis features
The main characteristics of homeostasis that should be known are:
- Process: at the beginning of homeostasis, the organism involved goes through a feedback process that can be positive or negative and in which the resulting cells end up with very different effects, but which are at the same time compensatory. When the feedback is positive, the effects of homeostasis are counteracted in the cells by returning to their original state. Whereas, if the feedback is negative, the response that occurs at the end, generates a significant change in the original structure of the cell.
- Regulation of body temperature: One of the most common functions of homeostasis is the regulation of body temperature. This is a symbol that the human body is kept at a perfect and adequate temperature. It is 97.6 degrees Fahrenheit or 36 Celsius. These values are called reference points.
- How Cold Affects Human Body Temperature: When the body temperature falls below certain limits, homeostasis ensures that the body warms up again. That is, the blood vessels contract or tighten due to the lack of heat, the skin contracts and the so-called “goose bumps” arises, the hairs stand up and take air from the skin offering an additional withdrawal against the cold. Sometimes the muscles also contract due to low temperatures causing a tremor that makes the body shake and warm up slowly.
- How heat affects body temperature: When there is a significant change in temperature, sensors in the skin transmit an alert to the hypothalamus, an area located in the brain. For example, if you go for a walk, your body heat would rise above the temperature set point. This occurs when the hypothalamus sends signals for your body to cool down. Mainly, blood vessels expand or dilate to help blood get closer to the surface of the skin. This allows more heat to escape from the body into the air. Then the sweat glands begin to produce more sweat. When sweat evaporates from the body, it creates a charming and refreshing effect.
- Regulation of blood sugar: By consuming carbohydrates such as bread and potatoes, the body transforms them into small sugars or glucose. Glucose is essential in the human body, because it is used as an energy source. Despite this, you cannot have too much or too little glucose in your blood. In this case the meaning of homeostasis is to maintain constant blood sugar levels.
Main types of homeostasis
The human body is a sublime machine, and much of it is because it keeps going in a variety of environments. Human beings are able to develop in very low temperatures, under diets and different lifestyles. Part of this condition of the body to adapt to these changes, is thanks to homeostasis, since the meaning of homeostasis is balance.
The types of homeostasis are:
Extension homeostasis
The definition of homeostasis in extension can be generated from a general point of view, that is, it is an allusion to a characteristic of any system, it can be open or closed, with which it can regulate the internal environment of the organism so that it is maintained stable.
Ecological homeostasis
It is a kind of dynamic balance which takes place between natural environments and their surroundings. The balance can disappear for multiple reasons including: floods, fires, earthquakes and any other natural disaster.
Ecological homeostasis represents then, the exchange that exists between different natural environments, allowing balance in an ecosystem; these are considered very necessary for survival. In the case of the planet in general, homeostatic balance is demonstrated in the relationship that exists between an ecosystem and the climatic changes that occur.
Ecological homeostasis is also known as ecological equilibrium, around 1950 it was questioned as some considered that constant and radical changes in populations were very frequent and that equilibrium was not a constant. In the same way they affirmed that these theories were replaced by the Theory of Chaos and the Theory of Catastrophes.
The ecological factors that negatively influence this homeostasis are earthquakes, storms, droughts and climate changes such as hot and cold waves.
Cybernetic homeostasis
This term was created in the mid-20th century by an English doctor named Williams Ross Ashby, who created a homeostat that regulates itself through feedback. That is, cybernetic homeostasis offers different electronic systems the ability to remain in balance.
Psychological homeostasis
When an imbalance occurs internally in human beings, it can also occur on a psychological level. So psychological homeostasis is the balance between human needs and satisfactions.
Psychological homeostasis is a kind of homeostasis that is a bit different and strange, totally unrelated to the reasons why biological homeostasis takes place. This assimilation depends on mental factors, stimuli of variables that are not considered entirely scientific, as they are so versatile that they do not allow a field of study to investigate them. These can be feelings, thoughts of anguish or anxiety, which define the way in which the body assimilates the process of homeostasis. This process can be affected by psychological problems, causing malnutrition diseases such as bulimia.
Oxygen homeostasis for the cellular process
When altitude is raised, the ambient oxygen in the atmosphere is less than that found on the surface. For this reason, respiration in an individual in these environments will end up being insufficient at a regular rate, the body through homeostasis intensifies the respiratory rate and then slowly increases the production of red cells in the blood.
Cell metabolism homeostasis
This type of homeostasis refers to the fact that the chemical composition of the internal environment of an organism must not undergo alterations and must remain unchanged. That is, the products formed by cellular metabolism will be discarded immediately, this type of process is present in the sebaceous and sweat glands, the lungs, although the most important is that carried out by the kidneys.
Homeostatic mechanisms
There are basically two types of homeostatic mechanisms that are:
The nervous pathways: whose function is the regulation of blood pressure in humans and mammals in general. It also regulates the concentration of oxygen and CO2 in the blood of human beings.
Endocrine pathways: in this case, it regulates the concentration of glucose in the blood. Also the regulation of the relationship between proteins, carbohydrates and fats. In addition to controlling the effects of fasting and feeding on the body.
Importance of homeostasis in humans
In the human body, the endocrine and nervous systems control homeostasis. Organs and systems provide feedback to the brain. The body maintains homeostasis by maintaining temperature, pH balance, electrolyte balance and water, breathing, and maintaining blood pressure.
When a person eats a meal that contains large amounts of electrolytes, such as table salt, the nervous system detects the electrolyte imbalance. The brain sends signals to the body to retain water and maintain electrolyte balance. Physically you can notice swelling in the feet, as well as thirst.
As the liquids are drunk individually, the electrolytes are diluted and in response to the increase in water, the cells release what already exists to maintain homeostasis. The kidneys then filter excess fluid and electrolytes from the system.
Homeostasis in the assimilation process incorporates a function of self-regulation of vitamins that interact with the body to convert them into energy to support life. This refers to a mechanism for the exit of the excess energy necessary to fulfill an efficient homeostasis. This regulates with the production of hormones what enters the body, examples of this choreography are the urinary tract, in which unnecessary filtered substances are released. The sweat and the glands responsible for the explosion of body fluids, this in order to keep the body at a standard temperature, while excess substances are released.
This functionality of the body is closely related to metabolism, since the assimilation of food will depend on the response that it has with respect to the outside. Climatic, atmospheric or simply external conditions can negatively affect the state of the body, but nevertheless, if homeostasis is being carried out in a correct way, the conglomerate of vitamins will act as energy to the body.
Homeostasis and the nervous system
Conservation of homeostasis
Biological systems, like the human body, are constantly out of balance. For example, when you exercise, muscles increase heat production and increase body temperature. In the same way, when you have a glass of fruit juice, your blood glucose increases. Homeostasis depends on the body's ability to detect and oppose these changes.
Cycles of negative feedback are often used to maintain homeostasis. These cycles act in opposition to the stimulus, or signal, that triggers them. For example, if the body temperature is too high, a negative feedback loop will act to lower it back to the reference value, or nominal value of 98.6 ° F / 37.0 ° C.
10 Examples of Homeostasis in Humans
Example 1: Acceleration of respiration
When human beings are exposed to low oxygen concentration environments, or when their blood oxygen levels are too low to meet cellular demand, for example when exercising, a response immediately arises that accelerates breathing seeking increase the amount of air breathed. At that time the heartbeat accelerates and blood pressure rises, providing a better supply of oxygenated blood in the body.
Example 2: Maintenance of glucose levels
Glucose is a class of sugar found in the bloodstream, but for a person to remain healthy, glucose levels need to be kept at the proper levels. If these levels rise, the pancreas secretes a hormone known as insulin and if, on the contrary, they remain very low, the liver transforms the glycogen in the blood into glucose, raising its levels.
Example 3: Balance of acids and bases
Human beings contain, in their body, chemical components called acids and bases, a balance between these is necessary to ensure that it works in an optimal way. The kidneys and lungs are two of the organ systems responsible for regulating these substances in the body.
Example 4: Body temperature
The internal body temperature of the human body is a good example of homeostasis. In a healthy body, body temperature should be 37 ° and it releases heat by controlling its temperature.
Example 5: Calcium control
Homeostasis regulates calcium levels in the human body. When these levels drop, the parathyroid releases hormone, if they are very high, the thyroid helps fix calcium in the bones and lowers its levels in the blood.
Example 6: Physical exercise
The physical activities cause the body to maintain homeostasis, sending lactate muscles to provide energy.
Example 7: Functions of the urinary system
Toxic substances that enter the blood suspend the body's homeostasis. However, it responds by getting rid of these through the urinary system. When an individual urinates it removes all toxins and other unpleasant components from the blood and homeostasis is restored to the body.
Example 8: Water level
More than 50% of the body weight of the human body is made up of water, homeostasis is responsible for maintaining the correct balance of the liquid. Cells that contain a lot of water swell in a way that they risk bursting, but those that contain too little can shrink. The human body must maintain a balance for none of these cases to occur.
Example 9: Arterial regulation
A body with healthy blood pressure is an example of homeostasis. When the heart detects changes in blood pressure, it sends signals to the brain and then receives cues on how to respond. When blood pressure is very high, the heart slows down, but if it is very low, it speeds up its movements.
Example 10: Lymphatic system and its functions
The human body is exposed to viruses and bacteria that can cause disease, the lymphatic system is responsible for attacking and helping to preserve homeostasis, fighting infection to maintain a healthy body.
