homeostasis

Homeostasis . Also known as homeostasis , it is the tendency of living organisms and other systems to adapt to new conditions and maintain balance despite changes. It is a compound word that comes from the Greek homeo or homo which means equal and stasis which means still.

Summary

[ disguise ]

• Introduction
• 2 Environment where it occurs
• 3 Features
• 4 Local mechanisms
• 5 Regional mechanisms
• 6 Central mechanisms
• 7 Cybernetic Homeostasis
• 8 Sources

Introduction

The interstitial fluid comes from the basal fluid and both are the extracellular fluid. The intracellular and extracellular fluids form the fluid of the entire body, which constitutes 60% of it. Much of the fluid leaves through the lymphatic vessels . To regulate balance there are regulatory mechanisms of homeostasis: local, regional and central.

In Biology, homeostasis is the state of dynamic equilibrium or the set of mechanisms by which all living beings tend to achieve stability in the properties of their internal environment and therefore the biochemical composition of fluids and cellular tissues , to maintain life , being the basis of physiology .

Environment where it occurs

Internal environment : The metabolism produces multiple substances, some of them waste that must be eliminated. To perform this function, organisms have excretion systems. For example, in man, the urinary system . Multicellular living beings also have Chemical Messengers such as Neurotransmitters and hormones that regulate multiple physiological functions.

External environment: Homeostasis, more than a certain state, is the resulting process of facing the interactions of living organisms with the changing environment whose tendency is towards disorder or entropy . Homeostasis provides living beings with independence from their environment by capturing and conserving Energy from the outside. The interaction with the outside is carried out by systems that capture external stimuli, such as the sense organs in higher Animals or systems to capture substances or nutrients necessary for metabolism, such as the respiratory or digestive system .

Characteristics

Homeostasis was discovered by Claude Bernard in the 19th century, but the term homeostasis was coined by the biologist Walter B. Cannon (1871-1945) who defined in 1932 the characteristics that govern homeostasis:

1. Importance of the nervousand endocrine systems in the maintenance of regulatory mechanisms.
2. Tonic level of activity: The agents of both the internal environment and the external environment maintain a moderate activity that varies slightly up or down, as if surrounding an average value in a range of physiological normality.
3. Antagonistic controls: When a factor or agent changes a homeostatic state in one direction, there is another factor or factors that tend to counteract the first with an opposite effect. This is what is called negative feedback or negative “feedback”.
4. Chemical signals can have different effects in different body tissues: Antagonistic homeostatic agents in one region of the body can be agonist or cooperative in other body regions.
5. Homeostasis is a continuous process that involves the registration and regulation of multiple parameters.
6. The effectiveness of homeostatic mechanisms varies throughout the life of individuals.
7. Tolerance: It is the ability of each organismto live in certain ranges of environmental parameters, which can sometimes be surpassed through adaptation and evolution.
8. A failure of homeostatic mechanisms produces disease or death. Situations in which the body cannot maintain biological parameters within its normal range, a diseasestate arises that can cause death.

Local mechanisms

It happens at the level of the interstitial space and consists of mechanisms or vascular responses such that when there is an increase in demand, vasodilation occurs and when there is less demand, there is vasoconstriction.

Responses will occur in the metabolism and body fluids. Mitotic index: percentage of cells that divide at a given time, mitosis is a local response to homeostasis.

Atrophy: when the components and number of cells decrease. Hypertrophy: Increase in cellular components due to increased demand, the mitochondria divide into two, the nucleus plus membrane systems. Hyperplasia: increased mitotic index.

Regional mechanisms

They are set in motion when local mechanisms do not guarantee balance. They are based on reflections and make the reflex arc act. For example, when you eat too much you feel like vomiting.

Central mechanisms

The thinking of action builds theories. Feedback processes: It can be positive or negative.

Positive: In the presence of a product, the synthesis of that product is stimulated. For example, the presence of oxytocin in the blood causes the hypothalamus to trigger the synthesis of that hormone.

Negative: A certain concentration of a final product causes the suppression of the antecedents.

Cybernetic homeostasis

In cybernetics, homeostasis is the feature of self-regulated systems, cybernetic systems that consist of the ability to maintain certain variables in a stationary state, of dynamic equilibrium or within certain limits, changing parameters of their internal structure.

In the 1940s, W. Ross Ashby ( 1903 – 1972 ) designed a mechanism that he called a homeostat capable of showing ultra-stable behavior in the face of perturbation of its “essential” parameters. Ashby’s ideas developed in Design for a Brain gave rise to the field of study of biological systems as homeostatic and adaptive systems in terms of dynamical systems mathematics .

This British researcher trained in Cambridge in [biology] and [anthropology], set guidelines and new approaches that have transcended other disciplinary fields such as [philosophy] and [epistemology] itself. He included this concept to explain the epistemological foundations that he proposes.

“Let us now talk about the problem of studying the communicational homeostasis of a family constellation. In general terms, it seems to us that families that have known schizophrenic members are closely homeostatic. Every living system undergoes changes at all times and day after day, so that It is conceivable to represent such changes by sinuosities of a curve in a multidimensional graph (or “phase space”) in which each variable necessary for the description of the states of the system is represented by one dimension of the graph.

Specifically, when I say that these families are closely homeostatic, I mean that the sinuosities of that graph or a certain point in phase space will span a relatively limited volume. The system is homeostatic in the sense that as it approaches the limits of its zones of freedom, the direction of its path will change such that the sinuosities will never cross the limits.”