Growth of the body and development of the body. Patterns of growth and development of the human body

The biological meaning of life is reduced to the reproduction of species. Here reproduction is considered as a barrier process leading from the adult organism to the newly formed one. In this case, only a small part of the organism is able to reproduce almost immediately, as it appeared itself. These are the simplest bacteria that can be divided in 20 minutes from the beginning of life. Others, in order to start multiplying, need to grow and develop.

The general concept of growth and development

So, living beings inhabit the planet and live on it. A huge number of them, which can not be counted, is reproduced within a day, weeks, months and years. Many for reproduction do not need to acquire new functions, that is, additional to those that they received after their appearance. But most others need this. They just need to grow, that is, increase in size, and develop, that is, acquire new functions.

Growth is called the process of increasing the morphological size of the body. The newly formed living entity must grow to start its metabolic processes at the most active level. And only with the increase in the size of the body can the emergence of new structures that guarantee the development of certain functions. Therefore, the growth of the body and the development of the organism are related processes, each of which is a consequence of each other: growth provides development, and further development increases the ability to grow.

Private understanding of development

Growth and development of the body are connected by the fact that they run parallel to each other. Previously it was understood that the creature must first grow up, and the new bodies guaranteeing the appearance of new functions will be located on the allegedly liberated place in the internal environment of the body. Approximately 150 years ago, there was an opinion that first there was growth, then development, then again growth and so on in a cycle. Today, understanding is completely different: the notion of the growth and development of the organism denotes processes that are not identical but flow together.

It is remarkable that in biology two types of growth are distinguished: linear and volumetric. Linear is called increasing the length of the body and its sections, and volumetric expansion of the body cavity. Development also has its differentiation. Identify individual and species development. Individual means the accumulation of certain functions and skills by a single species organism. A species development is the improvement of a new species, capable, for example, of adapting slightly to living conditions or populating previously uninhabited zones.

Ratio of growth and development in unicellular organisms

The lifespan of unicellular organisms is the time that the cell can survive. In multicellular this period is much longer, and that is why they are developing more actively. But single-celled (bacteria and protists) are overly volatile creatures. They actively mutate and can exchange genetic material with representatives of various strains of the species. Therefore, the development process (in the case of the exchange of genes) does not require an increase in the size of the bacterial cell, that is, its growth.

However, once a cell receives new hereditary information by exchanging plasmids, protein synthesis is required. Heredity is information about its primary structure. It is these substances that are the expression of heredity, since the 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 does not harm at all, then cells with such information die, because they are less viable than others.

The Biological Importance of Human Growth

Any multicellular organism is more viable than a unicellular organism. In addition, it has many more functions than one isolated cell. Therefore, the growth of the body and the development of the body are concepts most specific for multicellular. Since the acquisition of a certain function requires the appearance of a certain structure, the processes of growth and development are as balanced as possible 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 is divided many times. Thus, there is growth, that is, an increase in size, necessary for development (appearance of new functions).

Growth and development of multicellular different classes

Once a person's body is born, the processes of growth and development are balanced among themselves until a certain period. It is called a stop of linear growth. The dimensions of the body are laid in the gene material, like skin color and so on. This is an example of polygenic inheritance, the laws of which have not yet been sufficiently studied. Nevertheless, normal physiology is such that the growth of the body can not continue indefinitely.

However, this is typical for mammals, birds, amphibians and some reptiles. For example, a crocodile can grow all his life, and his body size is limited only by the life span and some dangers that may be waiting for him in its current. Plants grow at all life, although, of course, there are artificially grown species, in which this ability is somehow oppressed.

Features of growth and development in the biological plan

The growth of the body and the development of the body are aimed at solving several problems that are related to the fundamental properties of all living things. First, these processes are necessary for the realization of hereditary material: organisms are born immature, grow, acquire the function of reproduction during life. Then they give offspring, and the cycle of reproduction is repeated.

The second meaning of growth and development is the settlement of new territories. No matter how unpleasant it was to be aware of this, nature in every form has a tendency to expand, 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 it is not so noticeable now. Basically, he has to deal with the natural shortcomings of his body and with the smallest pathogens of diseases.

Basics of Growth

The concepts of "body growth" and "body development" can be considered much deeper. For example, growth is not only an increase in size, but also a multiplication of the number of cells. Each body of a multicellular organism consists of a set of elementary components. And in biology, the elementary units of the living are the cells. And although viruses do not have cells, but are still considered alive, this concept should be revised.

Let it be, but the cell is still the smallest of all balanced systems that can live and function. In this case, the increase in the size of the cell and the supracellular structures, as well as an increase in their number, is the basis of growth. This applies to both linear and volume growth. Development also depends on their number, because the more cells, the larger the size of the body, which means that the more spacious areas the body can colonize.

The Social Importance of Human Growth

If we consider the processes of growth and development only on the example of a man, then there is a kind of paradox. Growth is important, because the physical development of man is the main driving factor of reproduction. Personality, physically undeveloped, is often unable to give a viable offspring. And this is a positive sense of evolution, although, as a fact, it is negatively perceived by society.

It is the presence of the society that is a paradox, because under protection even a physically undeveloped person can marry and give offspring because of enviable intellectual abilities or other achievements. Of course, normal physiology does not change its principles in people who do not have diseases, but physically less developed than others. But it is obvious that the size of the body is the genetic dominant. If they are less, then the personality is less capable of adapting to changing habitat conditions than others.

Human development in society

Although a person has adapted the living conditions to himself, he still faces unfavorable factors. Survival in them is a matter of fitness. But here there is another biological paradox: today a person survives in society. It is a conglomeration of people that equates everyone's chances of survival in certain situations.

Here, too, biological instincts of species conservation work, so in the most horrific situations, few of the individuals care only about themselves. Therefore, since it is profitable for us to stay in the society, it means that the development of the human body without it is impossible. Man has even developed a language for communication in society, and therefore one of the stages of personal and species development is his 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 finds himself in the language environment, he adjusts, speaks 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 a society and without adaptation to living in it, people are least adapted to life in the prevailing conditions.

Periods of development of the human body

Each organism, especially multicellular, has a number 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 entire process of growth and development from a single-celled zygote to the body takes 9 months. After birth, the first stage of the life of the organism begins outside the mother's womb. It is called the period of the newborn, which lasts 10 days. The next one is the infants (from 10 days to 12 months).

After infancy, an early childhood begins, which lasts up to 3 years, and from the age of 4 to 7, an early childhood period begins. From 8 to 12 years in boys, and in girls under 11 years of age lasts a period of late (second) childhood. And from 11 years to 15 girls and from 12 to 16 boys have a teenage period. Young boys become 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, already from the teenage period to call the heirs of children wrong. They are young men, who from the age of 22 to 35 experience the first mature age. The second mature in men starts from 35 and ends at 60, and in women from 35 to 55 years. And from the age of 60 to 74 years old age begins . Age physiology is very indicative of changes occurring in the body of a person with the course of life, but diseases and features of life of elderly people engaged in geriatrics.

Despite the medical measures, the mortality rate during this period is the highest. Since the physical development of man here ceases and tends to involution, then bodily problems become more and more. But development, that is, the acquisition of new functions, practically does not stop, if we consider in the mental plane. In terms of physiology, development, of course, also tends to involution. It reaches a maximum in the period from 75 to 90 years (senile) and lasts for long-livers who have overcome the age barrier in 90 years.

Features of growth and development in periods of life

Age physiology reflects the features of development and growth in different periods of life. It focuses on biochemical processes and important mechanisms of aging. Unfortunately, there is no way to effectively influence aging, so people are still dying because of the damages accumulated during their life. The growth of the body ends after 30 years, and, according to many physiologists, already in 25 years. At the same time, physical development also stops, which can be restarted with hard work on oneself. In different periods of development should work on themselves, because this is the most effective evolutionary mechanism. After all, even strong genetic inclinations can not be realized without training and practice.