The biological meaning of life comes down to the reproduction of species. Here, reproduction is considered as a barrier process leading from an adult organism to a newly formed one. At the same time, only a small part of organisms is able to reproduce almost immediately, as it appeared itself. These are the simplest bacteria that are able to divide after 20 minutes from the beginning of life. Others, in order to begin to multiply, need to grow and develop.
General concept of growth and development
So, living beings populate the planet and live on it. Their huge number, which cannot be counted, is reproduced within days, weeks, months and years. For reproduction, many do not need to acquire new functions, that is, additional to those that they received after their appearance. But most others need it. They just need to grow, that is, increase in size, and develop, that is, acquire new functions.
Growth is called a processincrease in the morphological size of the organism. A newly formed living being must grow in order to run its metabolic processes at the most active level. And only with an increase in body size is it possible for new structures to appear that guarantee the development of certain functions. Therefore, the growth of an organism and the development of an organism are connected processes, each of which is a consequence of each other: growth ensures development, and further development increases the ability to grow.
Private understanding of development
The growth and development of the organism are connected by the fact that they run parallel to each other. Previously, it was understood that the creature must first grow up, and new organs, which guarantee the emergence of new functions, will be located in the supposedly freed place in the internal environment of the body. Approximately 150 years ago, there was an opinion that first there is growth, then development, then growth again, and so on through the cycle. Today, the understanding is completely different: the concept of growth and development of the body means processes that, although not identical, but flow together.
It is noteworthy that in biology there are two types of growth: linear and volumetric. Linear is an increase in the length of the body and its sections, and volumetric is the expansion of the body cavity. Development also has its own differentiation. Allocate individual and species development. Individual implies the accumulation of certain functions and skills by one organism of the species. And species development is the improvement of a new species, capable, for example, of adapting a little better toliving conditions or populate previously uninhabited areas.
The ratio of growth and development in unicellular organisms
The lifespan of single-celled organisms is the period that a cell can live. In multicellular, this period is much longer, and that is why they develop more actively. But unicellular (bacteria and protists) are too volatile creatures. They actively mutate and can exchange genetic material with representatives of different strains of the species. Therefore, the process of development (in the case of gene exchange) does not require an increase in the size of the bacterial cell, that is, its growth.
However, as soon as the cell receives new hereditary information through the exchange of plasmids, protein synthesis is required. Heredity is information about its primary structure. It is these substances that are the expression of heredity, since a new protein guarantees a new function. If the function leads to an increase in viability, then this hereditary information is reproduced in subsequent generations. If it does not carry any value or even harms, then cells with such information die, because they are less viable than others.
The biological significance of human growth
Any multicellular organism is more viable than a unicellular one. In addition, it has many more functions than a single isolated cell. Therefore, the growth of an organism and the development of an organism are the most specific concepts for multicellular organisms. Since the acquisition of a certain function requires the appearance of a certain structure, thenthe processes of growth and development are maximally balanced and are mutual "engines" of each other.
All information about the abilities to which development is possible is embedded in the genome. Each cell of a multicellular creature contains the same genetic set. In the early stages of growth and development, one cell divides many times. This is how growth occurs, that is, the increase in size necessary for development (the emergence of new functions).
Growth and development of multicellular different classes
As soon as the human body is born, the processes of growth and development are balanced among themselves until a certain period. It's called linear growth arrest. The size of the body is embedded in the genetic material, as is the color of the skin and so on. This is an example of polygenic inheritance, the patterns of which have not yet been sufficiently studied. However, normal physiology is such that body growth cannot continue indefinitely.
However, this is typical mainly for mammals, birds, amphibians and some reptiles. For example, a crocodile is able to grow throughout its life, and its body size is limited only by its lifespan and some of the dangers that may await it during its course. Plants do grow all their lives, although, of course, there are artificially grown species in which this ability is somehow inhibited.
Features of growth and development in biological terms
The growth of the organism and the development of the organism are aimed at solving several problems that are related to the fundamentalproperties of all living things. First, these processes are necessary for the realization of hereditary material: organisms are born immature, grow, and acquire the function of reproduction during their lifetime. Then they give birth, and the reproduction cycle itself is repeated.
The second meaning of growth and development is the settlement of new territories. No matter how unpleasant it is to realize this, but nature in each species has a tendency to expansion, that is, to populate as many territories and zones as possible. This gives rise to competition, which is the engine of species development. The human body also constantly competes for its habitats, although this is not so noticeable now. Basically, he has to deal with the natural defects of his body and with the smallest pathogens.
Basics of Growth
The concepts of "growth of an organism" and "development of an organism" can be considered much deeper. For example, growth is not only an increase in size, but also an increase in the number of cells. Each body of a multicellular organism consists of many elementary components. And in biology, the elementary units of living things are cells. And although viruses do not have cells, but are still considered alive, this concept should be reconsidered.
So be it, but the cell is still the smallest of all balanced systems capable of living and functioning. At the same time, an increase in the size of the cell and supracellular structures, as well as an increase in their number, is the basis of growth. This applies to both linear andbulk growth. Development also depends on their number, because the more cells, the larger the body size, which means that the more spacious territories the body can inhabit.
The social significance of human height
If we consider the processes of growth and development only on the example of a person, then a certain paradox appears here. Growth is important because the physical development of a person is the main driving factor in reproduction. Physically undeveloped individuals are often unable to give viable offspring. And this is the positive meaning of evolution, although, as a fact, it is negatively perceived by society.
It is the presence of society that is a paradox, because under its protection even a physically undeveloped person, due to enviable intellectual abilities or other achievements, is able to marry and give offspring. Of course, normal physiology does not change its principles in people who do not have diseases, but are physically less developed than others. But it is obvious that body size is a genetic dominant. Since they are smaller, it means that a person is less able to adapt to changing living conditions than others.
Development of a person in society
Although a person has adapted living conditions for himself, he still faces adverse factors. Survival in them is a matter of fitness. But there is another biological paradox here: today man survives in society. This is a conglomerate of people who equalizes the chances of everyone to survive in certain situations.
The biological instincts of species preservation also work here, therefore, in the most horrific situations, few individuals care only about themselves. Therefore, since it is beneficial for us to stay in society, it means that the development of the human body is impossible without it. Man even developed a language for communication in society, and therefore one of the stages of personal and species development is its study.
From birth, a person is not able to speak: he only makes sounds that demonstrate his fear and irritation. Then, as he develops and stays in the language environment, he adapts, says the first word, then enters into full-fledged speech contact with other people. And this is an extremely important period of its development, because without society and without adaptation to living in it, a person is the least adapted to life in the current conditions.
Periods of development of the human body
Each organism, especially multicellular, goes through a series of stages in its development. They can be considered on the example of a person. From the moment of conception and the formation of a zygote, he goes through the stages of embryogenesis and fetogenesis. The whole process of growth and development from a single-celled zygote to an organism takes 9 months. After birth, the first stage of the life of the organism outside the mother's womb begins. It is called the neonatal period, which lasts 10 days. The next one is infancy (from 10 days to 12 months).
After infancy, early childhood begins, which lasts up to 3 years, and from 4 to 7 years, early childhood begins. From 8 to 12 years old in boys, and in girls up to 11 years old, the period of late (second)childhood. And from 11 to 15 for girls and from 12 to 16 for boys, adolescence lasts. Boys become young men from the age of 17 to 21, and girls - from 16 to 20 years. This is the time when children become adults.
Adolescent and adult period
By the way, from adolescence it is wrong to call heirs children. They are young men who from 22 to 35 years old experience the first mature age. The second mature in men starts at 35 and ends at 60, and in women from 35 to 55 years. And from the age of 60 to 74, old age begins. Age-related physiology very revealingly reflects the changes that occur in the human body over the course of life, but geriatrics deals with diseases and features of the life of the elderly.
Despite medical measures, mortality during this period is the highest. Since the physical development of a person here stops and tends to involution, there are more and more bodily problems. But development, that is, the acquisition of new functions, practically does not stop, if considered mentally. In terms of physiology, development, of course, also tends to involution. It reaches a maximum between 75 and 90 years of age (senile) and continues in centenarians who have overcome the age barrier of 90 years.
Features of growth and development in periods of life
Age-related physiology reflects the features of development and growth in different periods of life. It focuses on the biochemical processes and important mechanisms of aging. Unfortunately, not yetopportunities to effectively influence aging, so people still die due to damage accumulated over a lifetime. The growth of the body ends after 30 years, and, according to many physiologists, already at 25 years. At the same time, physical development also stops, which can be restarted with hard work on oneself. In different periods of development, one should work on oneself, because this is the most effective evolutionary mechanism. After all, even strong genetic inclinations cannot be realized without training and practice.
