The science of biology includes a lot of different sections, smaller, but very important, specializing in some specific problems of disciplines. This makes it so vast and globally significant for humanity that it is simply impossible to overestimate its influence.
Embryology has become one of these important sciences. This is a fairly old discipline, the concept of which and the history of formation, we will consider in this article.
The concept of embryology science
Embryology is not just a biological discipline. This is a whole science that studies the formation, development and formation of embryos of living creatures from the moment of germination of cells and their fusion until the birth of a new organism.
All these processes are very important, their correct and normal course is vital . Therefore, the goal that this science sets itself is to study all the issues and mechanisms associated with embryos, their life, education and development.
Based on the goal, the tasks of embryology are the following points.
- Consider cell division processes.
- Identify patterns of formation in the embryos of primary lobes and body cavities.
- Trace the options for the formation of the axes of symmetry of the body of the future organism.
- Features of the formation of cavities of coelom and derivatives thereof.
- The formation of membranes around the embryo.
- The formation of a whole system of organs by which this or that organism is ultimately identified.
Thus, it becomes clear what embryology is. This is a narrowly specialized science about the intrauterine development of embryos from the moment of their formation to the birth of the light. As well as the study of issues related to the processes of gametogenesis, that is, the formation of germ cells.
Etymology of the word
The meaning of the word "embryology" is quite simple. Indeed, in Latin the word "germ" is pronounced as embryon, and the second part of the word logos is a doctrine. So it turns out that the name of science reflects all its deep meaning, the subject of study is briefly expressed.
In all modern dictionaries, the meaning of the word "embryology" is similar. It is almost the same as in translation from Latin. Add something new complicated. What does embryology mean? There is only one answer in all sources - the science of pre-embryonic and embryonic development of animals, humans and plants.
History of the development of science
The history of embryology dates back to antiquity. One of the first to speak about research in this area was Aristotle. His observations consisted in a study of the formation of an embryo of a chicken egg. This was the beginning of the development of the science in question.
Later, by the XVI-XVII centuries, scientists who were representatives of this discipline were divided into two camps according to theoretical views on the formation of embryos, and in general the origin of new organisms.
So, there were:
- theory of preformism;
- epigenesis.
The essence of the first is as follows: all the structures of the future organism do not develop over time, but already exist in a very reduced form, either in the ovum (ovists) or in the sperm (animals). And with the course of life and the development of the embryo, they simply increase in size due to the resulting nutrients.
Such views were, of course, erroneous. However, they existed almost until the middle of the XIX century. Adherents of these views among scientists of different time periods were:
- Marcelo Malpigi.
- J. Swammerdam.
- S. Bonnet.
- A. Galler.
- A. Levenguk.
- I.N. Liberkun and others.
The second theory in the history of the development of embryology, which also adhered to a significant number of bright heads of different times, is called epigenesis. Supporters of her believed that the body begins its development only after the ingress of germ cells into each other. In this case, there is nothing ready in the resulting embryo. Structures, future organs are formed gradually, from internal tissues.
Representatives who held these views were:
- W. Harvey.
- G. Leibniz.
- Friedrich Wolf.
- Karl Baer and others.
In the confrontation between these two camps, numerous data of embryology were accumulated, because scientists constantly conducted research, experiments, collected theoretical material.
Beginning in the mid-19th century, preformist views were dealt a crushing blow by the following discoveries.
- The Karl Baer germline resemblance law. In it, he says that the earlier the embryo is located, the more it looks like similar structures in other representatives of wildlife.
- Wolf described the basics of morphogenesis in the chicken germ , proving their gradual formation.
- The work of C. Darwin, in which he describes his views on the problem of the origin of species.
The result was the gradual formation of science as we see it today. The following scientists of the XIX-XX centuries made a great contribution to the development of discipline:
- Kovalevsky.
- Mechnikov.
- Haeckel.
- Wilhelm Roux and others.
Classification
The main sections of this science can be identified by the following points.
- Comparative embryology.
- Experimental
- The total.
- Ecological.
According to the type of studied organisms, embryology is also divided into:
- vegetable;
- an animal;
- person.
Each section has its own goals, objectives and objects of research, which are of great theoretical and practical importance in understanding the mechanisms of life. Embryology of animals is a very significant branch of science in agriculture and animal husbandry.
The structure of general embryology
General embryology is engaged in the study and comparative analysis of the embryos of all organisms at different evolutionary stages of planetary development. The result is a wealth of factual material proving the unity of origin of all living things on our planet.
The field of study of this discipline includes the study of gametogenesis processes. Embryology data is important in the health of the future generation, so this science is given special attention.
Characteristics of Comparative Embryology
The main method of comparing data in this discipline is analysis. Comparative embryology studies the embryos of animals, plants or humans in order to ascertain the similarities or origins of development.
Its founder was Karl Baer, who discovered the human egg and formulated the first law on embryos. A great contribution to the development of knowledge of the discipline was made by Haeckel. His biogenetic law has been universal for a long time. Comparative embryology has accumulated evidence supporting this feature.
Simply put, the essence was as follows: each embryo undergoes many stages in the process of its development. All of them in aggregate are a repetition of the general course of evolution that all organisms went through during the formation of living things on the planet.
Hence, such a similarity in the structure of embryos in all classes of animals: fish, amphibians, reptiles, birds and mammals. However, according to modern data, Haeckel’s law is not universal. After all, he does not explain why insect larvae and their adults differ so much among themselves, especially when it comes to incomplete transformation.
Another point that has been carefully studied by embryologists is mutation. So, it was proved that the earlier chromosomal problems occur, the greater their effect will be in the external manifestation after the formation of the organism. That is, the later the stage undergoes a mutation, the less it will be noticeably phenotypically in an adult.
Animal embryology
This section is important in the development of agriculture. The subject of study is the stage of formation of animal embryos. They are as follows:
- implantation;
- gastrulation;
- morula;
- blastula;
- neurula;
- intussusception.
That is, animal embryology is the same as all its other sections, only a more specialized area on the object of study. She also examines mutations in the process of embryogenesis, laws and mechanisms of their formation, looks for ways to prevent and solve various problems. For example, diseases of animal organisms.
This is of great importance for poultry, livestock, fish farming, solving veterinary issues and problems of insemination of animals.
The importance of advances in embryology
The most global achievement of modernity that embryology has been able to give people is the prognosis of infertility and detailed monitoring of all stages of the formation of human embryos. After all, this allows either to avoid the birth of children doomed to genetic diseases, or to correct future mutational changes with medical intervention.
Today, every pregnant woman is under the close supervision of doctors who, with the help of special equipment, can monitor and predict any situations in the development of the fetus.
Prospects for the development of this science
The main merits of this science are, of course, yet to come. After all, the development of technical means does not stand still, and modern technologies allow you to intervene during almost all known life processes.
In the future, it is possible to discover such processes at the stage of embryonic development that will help to avoid fetal diseases, eliminate the phenomenon of infertility and save people from many pressing problems.