Russian physiologist Ivan Pavlov owns a comparison of science with construction, where knowledge, like bricks, creates the foundation of the system. So the cellular theory with its founders - Schleiden and Schwann - is shared by many naturalists and scientists, their followers. One of the creators of the theory of the cellular structure of organisms R. Virchow once said: "Schwann stood on Schleiden’s shoulders." It is about the joint work of these two scientists that will be discussed in the article. On the cellular theory of Schleiden and Schwann.
Matthias Jacob Schleiden
At the age of twenty-six, the young lawyer Matthias Schleiden (1804-1881) decided to change his life, which did not please his family at all. Having abandoned the practice of law, he is transferred to the medical faculty of the University of Heidelberg. And at the age of 35, he became a professor at the Department of Botany and Plant Physiology at Jena University. Schleiden saw his task in unraveling the mechanism of cell reproduction. In his works, he correctly identified the primacy of the nucleus in the processes of reproduction, but did not see any similarities in the structure of plant and animal cells.
In the article "On the Question of Plants" (1844), he proves the commonality in the structure of all plant cells, regardless of their location. The review of his article is written by the German physiologist Johann Muller, whose assistant at that time was Theodor Schwann.
Failed priest
Theodor Schwann (1810-1882) studied at the Faculty of Philosophy at Bonn University, as he considered this particular area closest to his dream - to become a priest. However, the interest in natural science was so strong that he graduated from Theodore University at the medical faculty. As an assistant to the aforementioned I. Müller, for five years he made so many discoveries that would be enough for several scientists. This is the detection in the gastric juice of pepsin, and the sheath of nerve fibers. It was he who proved the direct participation of yeast in the fermentation process.
Companions
The scientific community of then-Germany was not too large. Therefore, the meeting of German scientists Schleiden and Schwann was a foregone conclusion. She took place in a cafe at one of the lunch breaks, in 1838. Future associates discussed their work. Matthias Schleiden and Theodore Schwann shared his discovery of cell recognition by nuclei. Repeating Schleiden’s experiments, Schwann studies animal cells. They talk a lot and become friends. And a year later, the joint work “Microscopic studies on the similarities in the structure and development of elementary units of animal and plant origin” appears, which made Schleiden and Schwann the founders of the doctrine of the cell, its structure and activity.
Theory of cell structure
The main postulate, which reflected the work of Schwann and Schleiden, is that life is in the cell of all living organisms. The work of another German - pathologist Rudolf Virchow - in 1858 finally bring clarity to the vital processes of the cell. It was he who supplemented the work of Schleiden and Schwann with a new postulate. “Every cell is from a cell,” he put an end to the questions of spontaneous generation of life. Many consider Rudolf Virchow to be a co-author, and some sources use the phrase "the cellular theory of Schwann, Schleiden, and Virchow."
Modern doctrine of the cell
One hundred and eighty years from that moment added experimental and theoretical knowledge about living things, but the basis remained the cellular theory of Schleiden and Schwann, the basic tenets of which are as follows:
- A self-renewing, self-reproducing and self-regulating cell is the basis and elementary unit of life.
- All living organisms on the planet are characterized by their identical structure.
- A cell is a complex of polymers that is reconstituted from inorganic components.
- Their reproduction is carried out by dividing the mother cell.
- The multicellular nature of organisms implies the specialization of elements in tissue, organ and systemic.
- All specialized cells are formed during the differentiation of totipotent cells.
Bifurcation point
The theory of German scientists Matthias Schleiden and Theodor Schwann was a turning point in the development of science. All branches of knowledge - histology, cytology, molecular biology, anatomy of pathologies, physiology, biochemistry, embryology, evolutionary teaching and many others - received a powerful impetus in development. The theory, which gives a new understanding of the interactions within a living system, has opened new horizons for scientists who immediately used them. The Russian I. Chistyakov (1874) and the Polish-German biologist E. Strasburger (1875) reveal the mechanism of mitotic (asexual) cell division. The discovery of chromosomes in the nucleus and their role in the heredity and variability of organisms, deciphering the process of DNA replication and translation and its role in protein biosynthesis, energy and plastic metabolism in ribosomes, gametogenesis and zygote formation follow.
All these discoveries in bricks enter the building of the science of the cell as a structural unit and the basis of all life on planet Earth. A branch of knowledge, the foundation of which was laid by the discoveries of friends and associates, which were the German scientists Schleiden and Schwann. Today, the armaments of biologists are electron microscopes with tens and hundreds of times solvability and sophisticated instruments, methods of radiation marking and isotope irradiation, genetic modeling technologies and artificial embryology, but the cell is still the most mysterious structure of life. More and more discoveries about its structure and activity bring the scientific world closer to the roof of this building, but no one will predict whether its construction will be completed and when. In the meantime, the building is not completed, and we are all waiting for new discoveries.