Individual development of the body. Process Features

Individual development of organisms - a setbiological processes that cause the growth and change of cells throughout the entire period of their existence. The common scientific name is ontogeny. Its main task is to observe, identify the main stages and characteristics of each period, identify patterns, and analyze the changes and identify the factors that these changes can cause.

individual development of the organism

Individual development of the organism is inherent not only to man, but to all living beings and plants. The main stages of development are:

  • Pre-embryonic development (gametogenesis).
  • Prenatal period of development (development of the embryo proper, embryogenesis).
  • Postnatal period (development from the moment of birth: growth, increment of mass,
    individual development of organisms
    regeneration, modification).
  • Gerontological period (aging).
  • The death of the organism (as a separate stage in ontogeny, death is not isolated, but any individual development ends exactly to it).

To consider the individual development of the bodyplants in this small article, we will not, but we will dwell on the development of representatives of the animal world closer to man. Stages of development, as already mentioned, do not change in a person and correspond to those mentioned above.

Human gametogenesis consists of twocomponents: spermatogenesis (maturation of male sex cells - spermatozoa) and oogenesis (maturation of female reproductive cells - oocytes). Fertilization is possible only under condition of mature sexual cells in male and female individuals. When pathologies arise in fertilization, organisms can be formed - chimeras, some of which are quite viable.

Human embryogenesis is one of the most important stages. It is divided into the initial stage (0 - 1 week after fertilization), actually the embryonic stage (2 - 8 weeks) and the fetal or fetal stage (9 weeks - birth). It is during this period that vitally important organs are formed, the body is made out, genetic or other pathologies can manifest themselves.

Individual development of the organism in postnatalthe period consists in the further development of organs, the increase in size and mass, the acquisition of new mental functions, the alteration of the motor activity and the development of its new species.

individual development
The postnatal period is the most important in developmenta new person. Its length is about 17 years (from newborn to adolescence). The individual development of the organism in this period is affected not only by features due to heredity, but also by psychological, social factors. Formation of consciousness, speech, thinking and other processes of higher nervous activity. By the end of this period, new individuals, as a rule, come with complete gametogenesis.

old age in the development of the body
Aging of the body - the stage of wilting, exhaustionall the resources of the body. There are irreversible disorders in nerve cells, myelin sheaths, visual and hearing quality decreases, vital organs "wear out", skin changes, the function of reproduction is lost, and tissue regeneration is dramatically slowed, etc.

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