Biography of Marcello Malpighi. Malpighi life story contribution to biology in brief
Malpighi Marcello is an Italian scientist, anatomist and physician who contributed to the development of medicine. How did he succeed in his work? What knowledge did you discover to people? What is Marcello's contribution to science? Who is Malpighi, what will his biography tell us? These questions will be of interest to physicians and university students, as well as to all readers of "Popularly about health" who seek to gain new knowledge.
Biography of Marcello Malpighi
Marcello Malpighi was born in a relatively small town located in the north of sunny Italy, Crevalcore, in 1628 on March 10. His mother is Maria Cremonini, father is Mark Anthony Malpighi. The boy Marcello was the firstborn, and soon after his birth, his brothers and sisters were born. In total, the family had 8 children. The family's income was rather modest, so it is not known how the boy's further fate would have developed if it were not for the fact that he lived in a town located near Bologna, which at that time was the scientific center of Europe. The neighborhood with this place gave the boy the opportunity to get a good education.
As a child, Marcello Malpighi was a very inquisitive and purposeful, gifted boy. This immediately caught the eye, and not only to relatives, but also to teachers. Marcello began his studies at school in 1640. There he studied Latin, Greek, exact sciences. Learning was easy for him. Five years later, when the young man was 17, he entered the prestigious University of Bologna, where he initially taught jurisprudence and philosophy, and later began to teach also medicine.
Marcello studied philosophy meticulously under the guidance of Professor Francesco Natali, who considered himself a follower of Aristotle. Unfortunately, after 4 years, family circumstances developed in such a way that the young man had to leave his studies at the university - three of his close relatives died at once - his father, mother and grandmother. Now the young man had to take care of his seven brothers and sisters. But the scientific biography of Malpighi did not end there. Father Marcello's brother eventually helped his nephew solve his problems and return to school.
A new round in the life of Marcello Malpighi
Upon returning to university, Marcello became interested in studying anatomy and natural history. Of particular interest to him were classes on the study of the structure of the human body, which at that time was taught by Bartolomeo Massari. Then there was a significant breakthrough in medicine - anatomists managed to obtain permission to open human corpses for research. Thanks to this, it became clear that the theories of Galen, the ancient Roman physician, that the body consists of liquid and solid parts, were shaken. A new understanding of human organs and tissues was opened, and it was this direction that was especially interested in Marcello Malpighi.
In 1653, the young man received a university degree and became a doctor of medicine. For some time he taught at the Bologna Higher School, but due to conflicts with colleagues he was forced to leave his job and move to Pisa. In this city, he became a professor at the Department of Theoretical Medicine. It was here that the scientist made the first important discoveries in his life, studying the structure of the human body. He studied blood, and also understood the work of the digestive and excretory systems of the body. Three years later, the professor returned to the city of Bologna, but he still did not succeed in teaching there for a long time due to various circumstances.
In 1662, the doctor began work in the city of Messina, where he was a professor at a local university. In 1666, Malpighi returned to Bologna and took up his former position, teaching theoretical medicine there until 1691. Then he became the personal doctor of Pope Innocent XII, and also continued teaching, but already at the papal college. Died Marcello Malpighi in 1694, November 29, two years after the death of his wife. This man made a great contribution to medicine, deepening the knowledge of mankind.
Malpighi's contribution to medicine
Malpighi paid much attention to the study of the structure of organs in humans and animals using a microscope. Although, at that time, he used a primitive device that magnified the image only 180 times, nevertheless the doctor managed to make several important discoveries. For example, the scientist discovered that the human body is permeated with many capillaries through which blood moves. Previously, no one could explain in what way the veins and arteries are connected to each other. In principle, if this was the only discovery of Marcello, then it would be enough to get into history, but the scientist was of little interest in this. He wanted to know. Therefore, he gave more to medicine, his contribution is somewhat broader.
Malpighi began to study the lungs and found that they are composed of tiny bubbles surrounded by capillary networks. It was about the alveoli.
The doctor was constantly looking for new knowledge. He tried to understand the nature of the fluids of the human body - urine and blood. The scientist was one of the first to describe the process of digestion and wrote a work on the effect of laxatives. In the process of studying, the doctor drew attention to the human kidneys. A close examination of their tissue helped to understand that small capillary glomeruli are present in the kidneys, which were later called Malpighian. The doctor's research also affected the spleen. In her tissues, the scientist found lymphatic bodies. Marcello Malpighi also studied the composition of the epidermis. He found that there were more layers under the stratum corneum and demonstrated the presence of a germ, second layer of skin. The doctor also studied flora and insect anatomy.
Marcello Malpighi devoted his entire life to scientific work, he was constantly interested in new knowledge and made discoveries that influenced the further development of medicine. The good knowledge he gained and an inquiring mind allowed Malpige to learn a lot, so his contribution is sufficient. People appreciated him and in honor of this respected person near the University of Bologna they erected a statue, perpetuating the memory of the Italian anatomist and doctor.
In the 17-18 centuries. important discoveries were made in the field of anatomy. The Englishman R. Lower described in detail (1664) the musculature of the heart. Lower was the first to experimentally establish the retarding effect of the vagus nerve on heart contractions. M. Malpighi studied the microscopic structure of the pulmonary alveoli, skin, liver, spleen and kidneys. The student of M. Malpighi A. Valsalva (1666-1723) is known for his works on the anatomy, physiology and pathology of the organ of hearing. N. Gaymor (1613-1685) carried out fundamental research on the anatomy of the male genital organs and paranasal sinuses. R. Graaf - on the anatomy and physiology of the female genital organs. T. Willis (1621-1675) described the structure of the brain, in particular its vascular system, and the accessory nerve that bore his name, as a clinician, he studied diseases associated with damage to the nervous system.
Miguel Servetus, Jerome Fabrice, Gabriel Fallopius, Leonardo da Vinci, A. Vesalius contributed to the development of anatomy as a science. Miguel Servet for the first time in Europe he described a small circle of blood circulation in his book "The Restoration of Christianity ..." 1553). After Servetus, research into the movement of blood continued tirelessly. R. Colombo studied the movement of blood in the lungs and described his observations in the work "On Anatomy in 15 Books" (1559). Jerome Fabrizius (Fabricius, Hiеronymua, 1533-1619) - a student of Fallopius and teacher of Harvey - was the first to demonstrate in an experiment (1603) and describe the venous valves, thereby proving the one-way movement of blood through the veins - towards the heart.
Bartholomew Eustachius in 1563 for the first time gave a detailed description of the organ of hearing in humans, including the auditory tube named after him, and Gabriel Fallopius studied the structure of the reproductive organs.
Malpighi Marcello (Malpighi Marcello. 1628-1694) - Italian physician and naturalist, founder of microscopic anatomy. Was born in Bologna. He studied medicine at the University of Bologna, in 1653 received a doctorate in medicine, was a professor in Bologna (1653), Pisa (1656), Messina (1662). In 1691 he was appointed physician-in-chief of Pope Innocent XII. Using lenses with 180x magnification, he studied the microscopic structure of tissues and organs of animals and plants. In 1661 he published "Anatomical observations of the lungs", in which he first described the pulmonary alveoli and capillaries, showing the path of passage of blood from the arteries to the veins. In the works "Anatomical study of the structure of the viscera", "On the spleen", "On the kidneys", "On the liver", "On the lungs" and others, he described the microscopic structure of these organs. In the embryological treatises "On the hatched egg" and "On the formation of a chick in an egg" he showed the development of the embryo, starting from the first hours of incubation; gave the first description of blastoderm, neural groove, eye vesicles, somites, bookmarks of blood vessels. M. Malpighi was engaged in microscopic studies of organs of animals and humans, as a result, a number of structures in histology bear his name - the Malpighian layer of the skin, Malpighian glomeruli of the kidneys, Malpighian corpuscles of the spleen, Malpighian papillae, etc. In 1661 he opened capillaries - the smallest vessels connecting arteries and veins.
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The discovery of the cell dates back to the period in the history of mankind when science first decided to throw off the title Ancillae theologiae(servant of theology) and when experimental natural science, responding to the demands of its time, claimed the title Dominae omnium scientiarum(madam over all sciences). It was the era of the dominance of the idea Francis Bacon(1561-1626) about the victory of man over nature, about a victory that can be achieved not by logical tricks and verbal formulations, but by experience and observation.
Inspired by this idea, a small group of people, beginning in 1645, began to gather in the evenings in different quarters of London in private apartments. These people lit their pipes and, in the light of oil lamps, discussed the charter of the new society they had conceived. These were the professors of two English universities, which were closed due to civil war, and simply lovers of art and natural experiments, which have become fashionable since the days of Galileo in Florence and F. Bacon in England.
The time was troubling. And although there were no political conversations at these meetings and only experiments from various fields of physics, chemistry, mechanics and life sciences were discussed, strict secrecy had to be observed. One of the initiators of the creation of the society, physicist R. Boyle (1627-1691), began to call the new organization "the college of the invisible."
In 1660, a charter was developed and a society was created to fight metaphysics and scholasticism, which took as its motto the dictum "Do not swear by the words of any teacher", or, in a nutshell, "Nothing at a word." Thus, the members of the society declared that in their activities they would not, as scholastics, rely on authorities like Aristotle or the fathers and teachers of the church, but would only recognize the evidence of scientific experience.
In 1662, a number of members of the "college of the invisible", having become influential people at the court of Charles II, achieved the approval by royal decree of the charter and the new name of the college - the Royal Society of London. Having replenished its staff with "completely free and unoccupied gentlemen", i.e. wealthy people, society received funds for printing the most important works in the form of separate books.
Among the first books printed was one that deserves our special attention. This is the work of a student of Boyle, the great master of natural experiments. Robert Hooke(1635–1703), who became a member of the Royal Society of London in 1663. Hooke was the inventor and designer of a wide variety of instruments, including an improved microscope.
For several years, he enthusiastically examined various small objects through this microscope, among which he once came across an ordinary bottle cap. Examining a thin section of the cork made with a sharp knife, Robert Hooke was struck by the intricate structure of the cork substance that was revealed when magnified. He saw a beautiful pattern of a mass of cells that resembled a honeycomb.
Knowing that cork is a plant product, Hooke began to study the same thin sections of branches and stems of various plants under a microscope. The first plant that came to his hand was an elderberry. On a thin section of its core, Hooke again saw a picture very reminiscent of the cellular surface of a honeycomb. Whole rows of small cells were separated from one another by thin partitions. He called these cells cells ( cellula).
This is how Hooke describes in Micrographia (1665) the story of his discovery.
“I took a piece of light, good cork and with a razor-sharp penknife cut the piece off and got a perfectly smooth surface that way. When I then carefully examined it with a microscope, it appeared slightly porous to me. I could not, however, with complete certainty recognize whether these were really pores, and still less to determine their shape. But on the basis of the looseness and elasticity of the cork, I, of course, could not yet draw a conclusion about the amazing structure of its tissue, which was revealed during further diligent study. With the same penknife, I cut an extremely thin plate off the smooth surface of the cork. By placing it on a black glass slide - since it was a white cork - and illuminating it from above with a plano-convex glass lens, I could see extremely clearly that it was all riddled with holes and pores, just like a honeycomb, only the holes were less correct. ; the resemblance to the honeycomb was further enhanced by the following features: first, the cork pores contained relatively very little dense matter in comparison with the empty spaces contained within them. So these walls - if I may call them that - or the partitions of these pores, in relation to the pores themselves, were about as thin as the wax partitions of honey cells (which consist of hexagonal cells) in relation to the cells themselves. Further, the pores, or cells, plugs were not very deep, but numerous. By means of special intermediate partitions, long pores were subdivided into rows of small, interconnected cells. The discovery of these cells, it seems to me, gave me the opportunity to find out the real and understandable reason for the peculiarities of the cork substance. These formations were the first microscopic pores that I saw and which were found by anyone at all, since I did not find any mention of them in any writer or researcher.
I counted the pores in the various rows and found that rows of about 50-60 of these narrow cells usually fit within 1 / 18th of an inch (1.44mm), from which I concluded that about 1,100 or slightly more than 1,000 would fit 1 inch long. , in 1 sq. inch - more than 1 million, or 1,166,400, and over 1200 million, or 1259 million, in 1 cubic meter. inch. It might seem incredible if the microscope did not convince us of this. These pores, I say, are so small that the atoms of which Epicurus was thinking would still be too large to pass through them. The cork fabric is nothing special; Examining under a microscope, I found that the core of an elder or almost any other tree, the inner tissue or the core of the hollow stems of various other plants, such as dill, carrots, turnips, etc., in most cases has the same kind of tissue which I just pointed out in a traffic jam. "
This is how the plant cell was first discovered. But in Hooke's head ideas for other inventions swarmed (spring clocks, improved compasses, etc.), and he transferred the further conduct of microscopic research to a member of the Royal Society Nehemiah Grew(1641-1712). In contrast to Guku, Gru was an extremely constant person and, having devoted all subsequent years of his life to the microscopic study of plants, discovered many new things in their internal structure. He presented the results of his research in a four-volume treatise, published in 1682, "Plant Anatomy with an Outline of the Philosophical History of the Plant World, and several other lectures read before the Royal Society."
Without dwelling on the description of Grue's innumerable observations, we present his general conclusions. In the body of plants, he distinguished dense and loose tissues: the latter, according to the terminology of Theophrastus, gave the name "parenchyma". Parenchyma, according to Gru, "Very similar in structure to beer foam or egg white foam, being, apparently, a liquid formation"... A completely different picture in Gru's descriptions was presented by dense tissues of stems and branches: "The presence of vertical and horizontal systems is clearly evident here, the interlacing of which gives a certain semblance of lace.".
This is how Gru describes these dense fabrics: “The most accurate and close comparison that we could now bring to clarify the essence of the structure of the body of a plant could be a comparison with a piece of thin lace woven by female hands on a bobbin cushion; indeed, both the core and its rays in the parenchyma of the cortex represent a beautiful picture of the finest lace. The fibers of the core are arranged in a horizontal plane, like a base in lace fabric, limiting individual bubbles of the core and bark, just like in lace, the threads are woven into meshes; the core rays are built without silt bubbles with very small, like dense pieces of lace or linen ...
... Then all the woody and air vesselsare located perpendicular to the horizontal fibers of all the above parenchymal parts: in the same way, in the lace on the pillow, the pins holding it are related to weaving. One has only to imagine the pins in the form of tubes and significantly increased in length, and the work on weaving lace, repeated many thousands of times in the same direction of increasing its thickness or height, in accordance with the height of the plant, and we will get a picture of the general structure of not only some or branches, but also every other part of the plant in its development from seed to seed. "
At the same time as Gru, an Italian naturalist began to study the microscopic structure of plants Marcello Malpighi(1628-1694). He turned to botany, having lost faith in the ability to immediately understand the complexity of the structure of the body of animals. Following the classical tradition of dividing all bodies of nature into the animal, vegetable and mineral worlds, he admits that he should have started by studying the latter, but "all life would not be enough for this."
The main merit of Malpighi is the accurate classification of the elements of the internal structure of plants. He distinguishes in the body of plants bubbles, or sacs, often filled with liquid and surrounded by a dense shell; fibers that are extremely small and visible only under a microscope; vessels. Malpighi's particular attention is drawn to the so-called spiral vessels, which he calls tracheas, equating them with the respiratory tubes (tracheas) of insects. Each of these groups of structural elements, says Malpighi, "Unites in a plant into separate parts of the plant body, homogeneous in structure" which he calls "tissues".
The word “fabric” emphasized the similarity of the internal structure of plants with the structure of linen and woolen fabrics. In recognizing this resemblance, Malpighi was in full agreement with Grue.
Working completely independently, both researchers came up with very similar results. They carried out the first systematic study of the internal structure of plants in the history of science, therefore they are deservedly awarded the title of "fathers" of microscopic anatomy of plants. At about the same time, both researchers presented their papers to the Royal Society of London, and one general meeting was scheduled for their hearing. This day, December 29, 1671, can be considered the birthday of plant anatomy.
Subsequent XVIII century. became the era of other requests for natural science. The economic life of the period of colonial development insistently demanded from botany to put in order the chaos in the names of plants, which was formed due to the influx of more and more types of plant raw materials from the captured overseas countries. Therefore, the attention of naturalists focused on the creation of a rational system of classification of the plant world. The study of the microstructure of a plant organism has receded into the background.
Throughout the XVIII century. there were no works similar to those of Malpighi and Gru. In a way, work was an exception. Kaspara WolF"Theory of Generation" (1759). Part of this work was devoted to the question of plant development. The very formulation of the problem of the genesis of plant tissues was a great step forward. But it was resolved in this work rather speculatively than through precise observations.
K. Wolf mistakenly believed that the growing part of the stem, leaf and root consists of a homogeneous gelatinous mass, in which new cells appear, "like gas bubbles in a dough that rises during fermentation." Over time, these bubbles increase in volume and number, which causes an external growth effect.
This theory, despite its extremely low validity, existed for a rather long time, and we still see traces of it throughout the entire first half of the 19th century.
The beginning of the 19th century marked by a number of interesting botanical works devoted to the cell. Three of them should be recognized as particularly important.
1. Opening L. Treviranus(1779-1864) a method of forming vessels from vertical rows of cells, the transverse partitions between which dissolve and disappear, and the entire vertical row of cells thus turns into one hollow vessel.
2. Opening D. Moldengauer(1766-1827) the method of the so-called maceration of tissues by treating them with hot nitric acid and other chemical reagents that dissolve the intercellular substance, as a result of which the entire tissue disintegrates into its individual cells.
3. Opening R. Brown(1773-1858) of the cell nucleus (1831), forcing researchers to begin to look closely at the contents of the cell. Previously, their exclusive attention was paid only to her shell.
So, by the 1830s. it turned out that the classification of Gru and Malpighi, which divided all the internal structural elements of the plant organism into three groups of formations - bubbles, fibers and vessels - does not correspond to reality. Fibers and blood vessels also turned out to be cellular formations, the parenchyma ceased to be Gru's “lace”, or “beer foam”, it disintegrated into individual cells under the action of acids, which means that the term “tissue” itself became very conditional.
The fabrics of plants actually turned out to be completely different from linen and woolen fabrics or lace, knitted from separate strands and threads. This visual effect arose due to the tight connection of the walls of adjacent cells, each of which was actually quite individual, connected with neighboring cells by a soluble intercellular substance. All formations in the plant organism were reduced to the basic form - the cell. The cell became the only element of the internal structure of plants. Such conclusions were voiced in the works P. Turpin(1775-1840), who wrote in 1828: “A plant is a complex personality; it is, in a way, an aggregate, consisting of a mass of private individuals, smaller and simpler. Each of the spherical bubbles or sometimes becoming hexahedral from mutual pressure, of which the cell tissue is composed, lives, grows and multiplies, not at all caring about what its neighbor is doing: it is, therefore, an independent vital center in the processes of growth and reproduction, it is - a cellular individuality, the association of which with a large number of similar individuals constitutes the largest part of the mass from which the complex individuality of the tree is formed. "
Approximately the same conclusions, but with regard to the structure of the animal organism, came at the beginning of the 19th century. and natural philosopher L.Oken(1779-1851), who believed that "The whole body of animals is made up of small constituent parts called ciliates"... But this view, which seemed not entirely justified, did not leave a noticeable trace in the science of that time. Finally, the idea of the unity of the cellular structure for the world of animals and plants was expressed in 1837 by a Czech physiologist J. Purkinje(1787-1869). He noted the correspondence of the granular (cellular) structure of animal organs to a clear division into cells of the plant body.
Thus, by the end of the 30s. XIX century, when the creators of the cell theory entered the arena of the history of science M. Schleiden(1804-1881) and T. Schwann(1810–1882), the concept of the cellular structure of organisms of the plant and animal world was not only prepared, but to a large extent also developed.
What, then, is the historical role of the founders of the cell theory?
In the works of Schleiden "Materials for the development of plants" and Schwann "Microscopic studies on the unity of structure and growth in animals and plants" for the first time it was shown and proved not only that all living things consist of cells, but most importantly, that all living things in all diversity comes (develops) from the cell. Neither Wolff nor Purkinje was able to unravel this truth, and they both imagined the process of cell development as the appearance of bubbles in an undifferentiated body mass, like a dough.
But Schleiden, of course, was mistaken in many ways. For example, he had insufficient and incorrect ideas about the contents of cells. He thought that the cell nucleus is located between the sheets of the double cell membrane, and could not figure out the substance inside the cell. Observing the cytoplasm, he did not understand that it, in fact, is the substrate of vital phenomena. He considered it a gum and allowed the appearance of mucous grains in it, turning into nucleoli and cell nuclei - cytoblasts, around which a new cell should appear. Schleiden overlooked or ignored the indications of the processes associated with cell division that were already available in science at that time.
Little remains of the concrete forms in which both Schleiden and Schwann envisioned the development of plants and animals. But the basic idea of cellular teaching in the formulation of Schleiden and Schwann, that "all living things originate from one cell, and at an early stage of its development, the embryo really consists only of a cell," and has retained its strength to this day.
The main drawback of the teachings of Schleiden and Schwann was excessive attention to the cell membrane and ignorance of the living contents of the cell (Schwann saw the membranes of animal cells even where they were not).
The importance of the living contents of a cell, called protoplasm, was first explained by Hugo Mole(1805-1872) in the article "On the movement of juices within cells", published in 1846.
“In a series of observations on the history of the development of plant cells that I made last summer, and the results of which, if they are confirmed by subsequent observations, I intend to publish later, I drew attention to the phenomena found by nitrogen-containing constituents of the cellular content ... Since this a viscous liquid appears wherever cells should be formed, preceding the first dense formations that indicate the place of development of future cells, we must admit that it also provides material for the formation of the nucleus and the primary cell membrane, and these formations not only stand in close connection with it in position, but show the same reaction to iodine. Since the process of the emergence of new cells begins with the isolation of sections of this viscous liquid, it seems quite correct to designate this substance by using the name related to its physiological function, and I propose for this the word protoplasm.
… The older the cell, the more the cavities filled with watery juice increase in it, in comparison with the mass of protoplasm. As a result, the mentioned cavities merge with each other, and the viscous liquid, instead of solid partitions, forms only more or less thick filaments that diverge from the mass surrounding the nucleus, like the atmosphere, towards the cell wall, bend here, connect with other filaments stretching in the opposite direction. direction, and in this way form a more or less densely branching anastomosing network ... When protoplasm forms such filaments, it is almost always possible to observe the movement of juices. "
After this study, which took away its inner layer from the cell membrane of the plant cell, which turned out to be a living layer of protoplasm containing the cell nucleus, the views on the process of cell reproduction, which Schleiden imagined as "a process taking place inside the cell membrane", obviously had to change.
We owe botany the correct ideas about the process of cell reproduction. F.Unger(1800-1870), who observed in 1841 the process of cell division in young growing organs of a plant, as well as exemplary studies of growth processes (mainly in lower plants) undertaken by K.Negeli(1817-1891). In 1842-1844. Negeli presented the results of his work in the article "Cell nuclei, formation and growth of cells in plants":
“For plants, the following law is valid: normal cell formation occurs only inside cells ... The content of the mother cell is divided into two or more parts. A shell is formed around each of these parts.
… On the basis of numerous studies on algae, fungi, horsetails, vascular opaque and phalogamous plants, I consider myself entitled to establish as a general law that here, in the mother's cell, two daughter cells are formed, or, in other words, one cell divides into two. I consider the opposite opinions and statements to be erroneous. "
The very complex processes of uniform distribution of nuclear matter, observed during cell division in higher plants, escaped the attention of the first researchers, and the honor of this remarkable discovery (1874), often mistakenly attributed to the German scientists E. Strasburger and W. Flemming, belongs to the Russian scientist I. D. Chistyakov(1843-1876). The history of this discovery, forgotten in the scientific literature, deserves that we dwell on it in more detail.
Young Russian botanist Ivan Dorofeevich Chistyakov, who escaped poverty, but because of constant deprivation "earned" consumption by the age of thirty, devoted his last years to unraveling the role of the nucleus in the process of cell division. Sparing no effort, he sat for months over the microscope, studying the development of horsetail and lymphatic spores.
A wonderful picture unfolded before him. Before maturation, the mother cells of the spores began to divide intensively. In this case, the contours of the cell nucleus disappeared, and the substance enclosed in the cell nucleus and later called chromatin (due to its ability to be strongly stained with aniline dyes) underwent a number of complex changes: at first it coiled into a ball resembling a ball of thread, then the thread rolled up into a ball broke into separate worm-like or horseshoe-bent segments; these segments were collected in a flat layer in the form of a belt in the middle of the dividing cell. Here, each shoe of chromatin material was neatly split along its length into two horseshoes, which diverged to opposite ends of the cell. Then, the two separated groups of horseshoes were folded into balls, and at two opposite ends of the dividing cell, first along the ball and then along the new daughter nucleus was formed. Finally, a septum appeared in the middle of the cell, and the mother cell was divided into two daughter cells.
Overcoming his illness, Chistyakov repeats his observations many times. With a weakening hand, he makes notes in a notebook and sketches of what he saw. In 1871, in the printing house of A.I. Mamontov, he publishes his work "The history of the development of sporangia and spores of the highest opaque anthers and pollen of phantom: anatomical and physiological research," and then publishes his discovery in 1874 and 1875. in European botanical journals in Italian and German, and it becomes the property of the entire scientific world. Famous German scientist E. Strasburger(1844-1912) realized that his Russian colleague had solved the riddle over which he himself had been struggling for so many years. Strasburger interpreted this neat cleavage of the horseshoe chromatin substance, which precedes cell division, this separation of the split halves to the opposite ends of the cell as a process associated with the hereditary transfer of the characteristics of the mother cell to daughter cells. Strasburger, who appreciated the tremendous significance of the fact described by Chistyakov, tried to ascribe to himself the priority of this discovery, but Chistyakov's printed works retained the honor of being the first. However, this honor, and financial assistance, and sending for treatment to Italy - everything turned out to be very late, and a year after the publication of the works, at the age of 34, Chistyakov died.
W. Flemming(1843-1905) only in 1878, four years after Chistyakov, made precise observations of the phenomenon discovered by Russian scientists, described it in detail and called it karyokinesis. Flemming also had the idea to call the nuclear substance, which undergoes changes in the process of karyokinesis, chromatin.
Chistyakov's research was continued by another Russian scientist - IN AND. Belyaev(1855–1911), who chose the cells of gymnosperm pollen as the object of his observations. He discovered the phenomenon of the so-called reduction division, which takes place during the maturation of male and female germ cells and consists in the fact that the number of chromosomes in each of the maturing germ cells becomes half the number of chromosomes in other cells of the plant body. Thus, in each of the mature sex cells, both male and female, by the time of maturation, only half the number of chromosomes is preserved. In the process of fertilization, when two cells, male and female, merge, the normal number of chromosomes is again obtained, which the mother cell transfers to all the cells of the body of the new plant that are formed from it.
Belyaev's discovery became one of the main arguments in substantiating the doctrine of the relationship of chromosomes with the process of hereditary transmission of the characteristics of parental cells to daughter cells. Pairwise connection during fertilization of the chromosomes of the male and female germ cells clearly explained why the descendants combine the hereditary characteristics of both parents. In the light of the doctrine of reduction division and chromosomes, many unclear until that time phenomena that accompany the inheritance of innate properties and traits in plants and animals became clear.
An experimental elucidation of the role of the nucleus in the cell was first carried out in the 1890s. Russian botanist I.I. Gerasimov(1867-1920). Experimenting with the alga Spirogyra, he obtained non-nuclear and binuclear cells. Cells without a nucleus could not exist for a long time, the presence of two nuclei caused increased development and cell division.
The glory of Russian researchers-cytologists was continued and brought to this day by work S.G. Navashina(1857-1930) and his many students. Navashin's work marked a new era in the study of the cell nucleus. He made a number of major discoveries, such as the discovery of satellites of chromosomes.
In the 1870s. a number of pseudoscientific theories appeared - a tendency arose to transform the theory of the cell into a theory of the structural elements of an adult organism. A crude mechanistic interpretation has become widespread, according to which cells are "separate, independent bricks" that make up the "complex architecture of a plant." So thought, for example, Rudolf Virchow(1821-1902), an outstanding German pathologist.
Prominent botanist and microbiologist F. Cohn(1828-1898) in his two-volume work "The Plant" one of the chapters was called "The State of Cells". In it, he equated the branches of a tree with the provinces, the leaves with the communities, and the cells with the personalities of individual citizens. He interpreted germination, flowering and fruiting as state functions, and vegetative reproduction as the emergence of autonomous colonies.
The famous German physiologist went even further along the path of similar analogies M. Vervorn(1863–1921), who equated the "state cellular structure" of the plant organism with the republic, as opposed to the "higher organization of animals" with their central nervous system, which reminded him of the "features of the monarchical cellular structure" dear to his heart. Vervorn believed that all physiology can be reduced to cell physiology, and tried to explain all complex physiological processes in multicellular living beings by a simple summation of what can be observed in amoebas and ciliates.
All these theories roughly schematized the structure of the organism, tried to reduce all life phenomena occurring in it to a simple arithmetic sum of the lives of individual particles - "cellular individuals". A natural reaction to the extremes of mechanism and vulgarization in the field of the doctrine of the cell was the speeches of individual scientists who proved the incorrectness of the absolutization of the role of the cell in the body and the impossibility of reducing the life of the organism as a whole to the sum of the lives of its constituent individual cells.
The largest turning point in science was the discovery in 1877 by Russian scientists I.N. Gorozhankin(1848-1904) plasmodesmata, or thin filaments of protoplasm, connecting through the pores the contents of neighboring cells. Plasmodesmata seem to bind the contents of individual cells of plant tissue into one whole. This important discovery prompted a number of European scientists, in particular the German scientist M. Heidenhain, to express considerations that "the concept of living matter is much broader than the concept of a cell and in any case does not coincide with it" (1912). Heidenhain recognized the intercellular substance as living.
If the mechanists - followers of R. Virkhov - portrayed the organism as complex, then the critics of the cell theory, in the heat of polemics, went to the other extreme and tried to present it as simple, like a solid plasmodium. At the same time, the fact that a multicellular organism develops from one cell by division, repeating the millennial stages of the evolution of the organic world, was ignored.
It is interesting to cite a historical background in connection with the oppositional statements of the "anti-cellulists", which were considered at one time ultra-revolutionary.
The earliest speeches of opponents of the cell theory in Russia were imbued with a clearly reactionary spirit. In 1901, at the 10th Congress of Russian Naturalists and Physicians, Deputy Minister of Public Education Lukyanov, who had previously headed the Department of Pathological Anatomy at one of the higher educational institutions and was considered a specialist in histology, made a speech. He began his speech at the congress with the question of the living intercellular substance, the presence of which supposedly refutes the cellular theory; He ended it with an indication of the "incomprehensibility of the mysteries of life" and a call for the union of science with religion. Professor of St. Petersburg University V. Shimkevich, who was sitting at the table of the congress presidium, at the end of this speech, demonstratively stood up and made the sign of the cross, saying aloud: "In peace, let us pray to the Lord."
The main in the doctrine of the cell, following the covenant of Schleiden and Schwann, is now considered the genetic side and the cell is considered as a biological unit of reproduction and differentiation of various tissues of the body. The new concept of the theory of the cell was enriched by a huge amount of new data obtained by science. However, even now, just as more than 100 years ago, the theory of the cell is the starting point for the study of any organism, including the plant organism.
In fact, the microscope was invented in 1609-1619, but who was its first designer is not exactly established. In 1610 or late 1609, the Italian astronomer Galileo first constructed a microscope while working to improve the telescope. At the same time Domitian (1610) proposed the name - "microskonium".
Later, in 1659, the brilliant scientist and mechanic Huygens invented a complex eyepiece for the astronomical tube; in 1672, the German physicist Johann Sturm (1635-1703) introduced a two-lens objective into the microscope instead of a single-lens one, and also invented a differential thermometer.
Microscopes of the 17th-18th centuries had obvious optical defects and gave obscure distorted images of microscopic objects. One had to have a very sophisticated ability to observe the microscopic world in order to make numerous discoveries that glorified for centuries the name of the first micrograph - Leeuwenhoek.
The first message from Levenguk, setting out the results of his amazingly accurate observations made with homemade microscopes (or rather, loupes with a mechanical device for focusing and with a magnification of up to 300 times), dates back to 1673. The history of medicine must acknowledge Levenguk's undoubted merit in the fact that he loved to work with a microscope, otherwise histology, microbiology, biology could be a whole century late.
Anthony van Leeuwenhoek (1632-1723), first was a town hall doorman in the Dutch city of Delft, then (from 1648) a student studying trade in Amsterdam. From 1660 until the end of his life, Leeuwenhoek held a number of municipal posts. He started microscopic research only in 1673. To this end, he created microscopes from lenses of his own grinding.
Two years later, Leeuwenhoek, examining a drop of water taken from a puddle under a microscope, discovered a world unknown before him of the smallest living creatures ("ciliates"), including bacteria. Observing the movement of blood in the capillaries, he described erythrocytes, the structure of smooth and striated muscles, bones, dentin of teeth, and the cellular structure of various plant organs. He also studied the fine anatomical structure of the smallest insects, the parthenogenetic reproduction of aphids. In 1677, Leeuwenhoek, together with his student L. Gamom, discovered human and animal spermatozoa.
In 1811, the German physicist Fraunhofer made an achromatic microscope with 4 objectives, but its shape was very inconvenient. For the first time an achromatic microscope in a satisfactory form was designed by the Dutch optician van Deijl in 1807. Sufficiently advanced microscopes began to be produced after the Parisian optician-mechanic Chevalier made a lens in 1824 from four achromatic lenses connected together.
And now imagine what kind of dexterity Dr. Malpighi needed to have in order to see and open the capillary blood supply, as well as describe the microscopic structure of a number of tissues and organs of plants, animals and humans? Therefore, it is not surprising that Malpighi, the owner of such a penetrating gaze, became one of the founders of microscopic anatomy.
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Marcello Malpighi, Italian physician and biologist, was born on March 10, 1628 in Crevalcore near Bologna. His father was Mark Antony Malpighi, a middle-class nobleman, and his mother was Maria Cremonini. At the age of 12, his father sent him to school, where the boy studied Latin, rhetoric and other subjects. Having discovered Marcello's extraordinary abilities, his father sent him in 1645 to Bologna, to the university. The first information Marcello received from Francesco Natali, professor of philosophy. For 4 years, the future scientist pored over the philosophy of Aristotle.
An unexpected misfortune in 1649 interrupted the teaching: one after another, Malpighi's father, mother and grandmother (father's mother) quickly died. As the eldest son, Marcello had to go to Crevalcore to arrange the affairs of his large orphaned family - he had four brothers and three sisters. After bothering for a while, Marcello left the business to complete his uncle, and he himself returned to the university.
The next subject was metaphysics, which Malpighi studied under the guidance of the Jesuit Father Gottard Belloni. On the advice of his first teacher, Natalie Marcello chose medicine for specialization, in which he was most attracted by anatomy. At the Faculty of Medicine, his main teachers were: in anatomy by Bartolomeo Massari, and in clinical medicine by Andrea Mariani.
After studying at the university, Marcello defended his dissertation for the degree of Doctor of Medicine in 1653. Three years later, he was entrusted with lecturing on medicine at the Bologna Higher School (Archiginnasio), but his enemies and envious people, one of whom was the professor of theoretical medicine Montalbani, so poisoned his life with their persecution that he willingly accepted the offer of the Duke of Tuscany Ferdinand II to take the newly established Department of Theoretical Medicine in Pisa. At the end of 1656, Professor Extraordinary Malpighi begins to lecture.
In the home of the professor of mathematics Alfonso Borelli, with whom Malpighi became close, anatomists performed dissections of animals. The Grand Duke of Tuscany Ferdinand and Prince Leopold were present at the anatomical autopsies and generally treated what was happening in the circle with keen interest. Later, they invited scientists to the palace for demonstrations. Thanks to the interest of the ruling officials in anatomy and physiology, the Experimental Academy was founded in 1657 by Prince Leopold and later gained great fame.
During this period, Malpighi conducts research on the nature of blood, writes works about urine, the effect of laxatives, and digestion. However, his work is interrupted by the news of a feud that broke out between his brother Bartolomeo and the neighboring family of Sbaralya, whose possessions bordered on the lands of the Malpighi family in Crevalcore. This swara, which has become chronic and has taken on very harsh forms, is destined to often invade the life of a scientist. Partly out of ill health, partly out of a desire to be closer to his home and family, Malpighi receives permission from the Grand Duke to return to Bologna. Here he again takes a professorship at the university.
Oh, that Italian temperament. At the end of 1659, another trouble hit Malpighi. His brother Bartolomeo and a representative of a hostile family, Dr. Tommazo Sbaraglia, met in the evening on one of the streets of Bologna and started a fight, during which Bartolomeo mortally wounded Tommaso with a stiletto blow. Bartolomeo was sentenced to death, but after serving a year and a half in prison until the litigation between the families ended, he was pardoned at the request of Malpighi.
In the second year after his return to Bologna, Malpighi was deeply grieved by the death of his second teacher Andrea Mariani (1661). In the same year, the Chair of Medicine in Messini was vacated after the death of Professor Pietro Costelli, and the Messianic Senate invited Malpighi to this chair. After receiving a four-year leave from the leadership of the University of Bologna, he left for Messina in October 1662. Here in Messina, Malpighi was primarily concerned with plant anatomy.
In 1684 Malpighi acquired a villa in Corticelli near Bologna. In the same year, misfortune befell him again: a fire broke out in his house in Bologna, which destroyed a significant part of his property, microscopes and a large number of manuscripts containing valuable scientific materials. In 1689, another misfortune befell him. In proportion to Malpighi's fame, Montalbani's dislike for him grew. Malpighi's ill-wishers, unable to harm his scientific reputation, decided to inflict material damage on him. One of the members of the Sbaralya family and a certain Mini, who repeatedly attacked Malpighi in polemical articles, organized a gang of young people that attacked a villa in Corticelli. As a result of the attack, the situation inside the house was destroyed, scientific instruments and materials were burned.
This incident finally drained the patience of 61-year-old Malpighi. He gave up lecturing and retired to his home. In 1691, Malpighi accepted the invitation of the Pope and went to Rome, where he was appointed the personal physician of Innocent XII.
In Rome, Malpighi was very ill, gout made itself felt. On July 25, 1694, he suffered an apoplectic stroke, after which he recovered and began to work, preparing his scientific works for publication. His wife died soon after. The death of a loved one caused him deep suffering, he was inconsolable. On November 29, 1694, a second apoplectic stroke followed, which took Malpighi's life a day later. Autopsy revealed a greatly enlarged heart and traces of hemorrhage in the cerebral ventricles. According to the will, the body was interred in Bologna. In honor of Malpighi, a medal was struck in Bologna, his statue was erected at the university and next to him, as if in mockery, was the statue of his enemy, Dr. Sbaralya.
Malpighi's activity was versatile: he was a pioneer in the field of histology, embryology, anatomy, botany, even mineralogy (he wrote an article on the origin of metals). Strictly speaking, he can be called the forerunner rather than the founder of these scientific disciplines. In addition, he was also a medical scientist and practical doctor, and a clinician, who was interested in diseases not only from the point of view of medicine, but also as a subject of study: he did not miss an opportunity to be present at autopsies of persons who died from certain diseases. and get acquainted with the diseases identified in their organs.
Dr. Malpighi's scientific achievements are enormous. He was the first scientist to engage in systematic and targeted microscopic research. This allowed him to make a number of important discoveries. So, in 1660, he described the alveolar structure of the lungs in a frog and blood cells in a hedgehog.
Being engaged in botany, Malpighi described air tubes (1662) and vessels (1671) in plants, published a major work "Plant Anatomy" (two volumes, 1675-1679). The family of dicotyledonous free-petalled plants (Malpigiaceae) is named after Malpighi.
The most important merit of Malpighi, of course, is the discovery of capillary circulation (the object of the study was the frog's bladder), which supplemented Harvey's theory of blood circulation. Malpighi was using a microscope, so he discovered something that Harvey could not see. Four years after the death of Harvey, that is, in 1661, Malpighi published the results of observations on the structure of the lung, and for the first time gave a description of the capillary blood vessels that connect arteries to veins. Thus, the last secret of the circulatory system was revealed.
Marcello Malpighi described the structure of the lung in detail, pointing out that it consists of countless small bubbles entangled in a network of capillary blood vessels. However, the scientist could not establish what is the role of the lungs in the body of an animal and a person. However, he categorically refuted Galen's theory of blood cooling; however, his opinion that the blood in the lungs mixes was also not true.
The discovery of capillary blood vessels and the description of the structure of the lungs are not the only merit of Malpighi. He gave a detailed description of the structure of the kidneys, in which he found glomeruli, later called Malpighian bodies:
1) in the kidneys of humans and vertebrates (with the exception of some fish), the glomeruli of arterial capillaries, in which fluid from the blood is filtered into the urinary tubules;
2) in the reticular tissue of the spleen there are lymphoid nodules in which lymphocytes are formed.
In addition, Malpighi described the structure of the skin, the growth layer of the epidermis of the skin and the microscopic structure of a number of tissues and organs of plants, animals and humans: lymphatic bodies of the spleen, pyramids and glomeruli in the kidney, excretory organs of insects. All these formations are named after him.
In conclusion, let us correct the mistake of medical historians and briefly mention the achievements of Malpighi's unjustly forgotten compatriot Francesco Stelluti (Stelluti, 1577-1651), an Italian scientist, physician and anatomist, and since 1603 a member of the Academy in Rome. He was one of the first to use the Galileo microscope with a concave eyepiece to study the anatomy of animals, in particular insects; first compiled in 1625 a detailed description of the structure of the bee, providing it with carefully executed drawings.
Marcello in 1653 defended his thesis for the degree of Doctor of Medicine. Three years later, he was entrusted with lecturing on medicine at the Bologna Higher School (Archiginnasio), but his enemies and envious people, one of whom was the professor of theoretical medicine Montalbani, so poisoned his life with their persecution that he willingly accepted the offer of the Duke of Tuscany Ferdinand II to take the newly established Department of Theoretical Medicine in Pisa. At the end of 1656, Professor Extraordinary Malpighi begins to lecture.
In the home of the professor of mathematics Alfonso Borelli, with whom Malpighi became close, anatomists performed dissections of animals. The Grand Duke of Tuscany Ferdinand and Prince Leopold were present at the anatomical autopsies and generally treated what was happening in the circle with keen interest. Later, they invited scientists to the palace for demonstrations. Thanks to the interest of the ruling officials in anatomy and physiology, the Experimental Academy was founded in 1657 by Prince Leopold and later gained great fame. During this period, Malpighi conducts research on the nature of blood, writes works about urine, the effect of laxatives, and digestion. However, his work is interrupted by the news of a feud that broke out between his brother Bartolomeo and the neighboring family of Sbaralya, whose possessions bordered on the lands of the Malpighi family in Crevalcore. This swara, which has become chronic and has taken on very harsh forms, is destined to often invade the life of a scientist. Partly out of ill health, partly out of a desire to be closer to his home and family, Malpighi receives permission from the Grand Duke to return to Bologna. Here he again takes a professorship at the university.
Dr. Malpighi's scientific achievements are enormous. He was the first scientist to engage in systematic and targeted microscopic research. This allowed him to make a number of important discoveries. So, in 1660, he described the alveolar structure of the lungs in a frog and blood cells in a hedgehog. Being engaged in botany, Malpighi described air tubes (1662) and vessels (1671) in plants, published a major work "Plant Anatomy" (two volumes, 1675-1679). The family of dicotyledonous free-petalled plants (Malpigiaceae) is named after Malpighi. The most important merit of Malpighi, of course, is the discovery of capillary circulation (the object of the study was the frog's bladder), which supplemented Harvey's theory of blood circulation. Malpighi was using a microscope, so he discovered something that Harvey could not see. Four years after the death of Harvey, that is, in 1661, Malpighi published the results of observations on the structure of the lung, and for the first time gave a description of the capillary blood vessels that connect arteries to veins. Thus, the last secret of the circulatory system was revealed. Marcello Malpighi described the structure of the lung in detail, pointing out that it consists of countless small bubbles entangled in a network of capillary blood vessels. However, the scientist could not establish what is the role of the lungs in the body of an animal and a person. However, he categorically refuted Galen's theory of blood cooling; however, his opinion that the blood in the lungs mixes was also not true. The discovery of capillary blood vessels and the description of the structure of the lungs are not the only merit of Malpighi. He gave a detailed description of the structure of the kidneys, in which he found glomeruli, later called Malpighian bodies:
- in the kidneys of humans and vertebrates (with the exception of some fish), the glomeruli of arterial capillaries, in which fluid from the blood is filtered into the urinary tubules;
- in the reticular tissue of the spleen there are lymphoid nodules in which lymphocytes are formed.
