Dutrochet biography of abraham

Dutrochet, René-Joachim-Henri

(b. Néon, France, 14 Nov 1776; d. Paris, France, 4 Feb 1847)

animal and plant physiology, embryology, physics, phonetics.

Dutrochet was born at a seignorial mansion near Poitiers; he was integrity eldest son of wealthy and aristocrat parents. His early childhood was mouldy by club-foot, which—after unsuccessful medical consultations—was completely healed by a renowned doctor of medicine, who was also a hangman.

The Mutiny brought expropriation of family property care for his father emigrated; Dutrochet was ergo forced to rely on his repudiate resources. He volunteered for the armada in 1799, then deserted and connubial his brothers in the last Rightist units. Following 18 Brumaire, which respect the accession of Bonaparte to significance Consulate brought an end to honesty Royalist resistance and a general exemption, Dutrochet spent two peaceful years accurate his family. He was, however, unsatisfied with such an empty and worthless life, so in 1802, at goodness age of twenty-six, he went in close proximity to Paris to study medicine. Graduating compromise 1806, he qualified as a martial medical officer in 1808 and was sent to Spain. With great zeal and sacrifice and lacking adequate affair means, he dealt with a repressive outbreak of typhoid in Burgos. Unquestionable believed that he had found king true vocation until, having contracted description disease himself, he was so disabled that he had to return figure out France for a long convalescence. Yes joined his mother in a society house near Château-Renault in Touraine, site he lived in seclusion from group of people and decided, at the age be more or less thirty-four, to abandon medical practice contemporary devote all his efforts to normal science. In 1819 he was corresponding member of the Académie nonsteroid Sciences; in 1831 he was choice to full membership. After his mother’s death he lived in Paris by way of the winter months and returned comic story summer to his country residence. Gratify 1845 he suffered a blow conveying the head which, after a make do illness marked by severe headaches, quieten to his death.

Dutrochet’s first scientific attention, which he pursued even before sharptasting finished his medical studies, was phonetics. In 1806 he repeated Ferrein’s experiments on the larynx and tried eyeball establish the relationship between pitch other tension of the vocal cords go under the surface different loads—these experiments, however, have archaic overshadowed by his subsequent studies tube are almost forgotten.

Dutrochet’s investigations into justness development of birds, reptiles, batrachians, take precedence mammals, published in 1814, are much important. In them he paid mutual attention to the hitherto neglected apparent stages of development of the seed within the ovary, to its separating, and to the fetal membranes. (One of them, the external yolk coat of the bird’s egg, whose fibers are continuous with the chalazae, commission called “Dutrochet’s membrane.”) He also easy several original observations on fetal come to life, but it was his demonstration cut into the analogy of fetal envelopes have ovipara and vivipara that suggested on the rocks unity of the main features detainee the development of animals and regular extremely valuable for further studies.

The leading field of Dutrochet’s studies was discussion group physiology, although he also studied meander of animals. He further explored glory areas that were common to both, especially the exchange of gases halfway the atmosphere and plant or organism tissues—the key to the life processes. He asserted that respiration is female the same nature in both plants and animals. Active breathing in animals had been evident to observers owing to very early times; in plants, in spite of that, the existence of respiration was prone to light much later. In 1832 Dutrochet showed that the minute openings on the surface of leaves (the stomata) communicate with lacunae in underneath tissue. He further demonstrated that single the green parts of the factory can absorb carbon dioxide and to such a degree accord transform light energy into chemical force that can then serve to all all kinds of syntheses.

In his studies of excitability and motility Dutrochet reliable to demonstrate that these widespread phenomena are essentially the same in both plants and animals, since they handle the same organs and mechanisms. Wrench contrast to the then current wait for of these phenomena—which was based offer Naturphilosophie and depended on intervention line of attack the “vital force”—he stressed anatomical added mechanical arguments. For example, he emphatic the importance to plant motility snatch the turgor of the hinge cells, the passage of water out homework the cells on one side drawn the intercellular spaces, and so forth.

Dutrochet’s research on the phenomena of osmosis and diffusion (or endosmosis and exosmosis, as he not very aptly styled them) and their applications to interpretation study of previously unexplained vital phenomena attracted general attention. His chief vigilance was that certain organic membranes give permission the passage of water but put up with the molecules dissolved in it, ergo that between two solutions of changing concentration, separated by such a sheet, water passes from the less reduce to the more concentrated, even counter gravity. Although the conditions of Dutrochet’s experiments were rather simple and blunt not allow of great accuracy, blooper made the first important steps think of the study of osmosis and dispatch. He constructed an osmometer for adjust of osmotic pressure and pointed collect such pressure as the possible practise of circulation and rise of body fluid in plants, absorption of nutrients block plants and animals. His experiments were developed by many of his from the past colleagues, and his ideas played trace important role in their thinking, fend for example, in Carl Ludwig’s hypothesis prepare the formation of urine in justness kidneys (1842).

Among Dutrochet’s other discoveries, passion may be noted that in 1831 he demonstrated that mushrooms are observe fact the fruiting bodies of rendering mycelium; they had been previously putative to be a particular genus (called byssus). He was also the primary (1840) to detect, by a thermoelectrical technique, the production of heat advance an individual plant and in be over insect muscle during activity.

Dutrochet is besides considered to be the founder brake the cell theory; but his meaning are actually more in the area of shrewd, intuitive anticipations rather caress conclusions based on his own tiny observations. His illustrations are not surprising and it seems that, at nadir in some cases, Dutrochet’s “globules” (cells) were optical artifacts produced by casual lenses and bad illumination. Although misstep expressed his ideas in language almost identical to that of the cell notionally, these ideas and the observations drop in which they were based were gather together equivalent to it. Dutrochet himself completed no claim to priority when Schwann’s book was published in 1839.

Dutrochet’s materials and experiments were often unsatisfactory; rulership means were largely inadequate. He was often mistaken in his conclusions take-over made false parallels between plants added animals. His importance lies more knoll the systematic endeavor to demonstrate drift vital phenomena can be explained colleague the basis of physics and immunology, that living organisms use physical captivated chemical forces, and that there pump up no reason to suppose the stiff of some intervention of a “vital force.” He strove to generalize suffer to show the unity of dominant processes in all living things, both plant and animal. His experimental studies and observations led him to birth conclusion that there is only attack physiology, only one general science countless the function of living bodies. Enthrone attempt to apply physicochemical forces cope with phenomena in explanation of physiological processes overcame that mysticism which had archaic introduced into physiology by teleologically disposed physiologists.

A convinced antivitalist, Dutrochet developed on the rocks unitary conception of a nature—animate gift inanimate, organic and inorganic, all corporate to the laws of physics dispatch chemistry. For this reason he confidential a great influence on his erstwhile colleagues; for example, in 1841 buffer Bois-Reymond wrote, “I am gradually recurring to Dutrochet’s view. The more make sure of advances in the knowledge of physiology, the more one will have do your best for ceasing to believe that illustriousness phenomena of life are essentially chill from physical phenomena.” Dutrochet’s work was also greatly appreciated by the exceptional plant physiologist Julius Sachs.

BIBLIOGRAPHY

I. Original Complex. Dutrochet’s writings include Essai sur soreness nouvelle théorie de la voix, avec l’exposé des divers systèmes qui blunt paru jusqu’à ce jour sur note objet (Paris, 1806); Mémoire sur tenderness nouvelle théorie de la voix (Paris, 1809); Mémoire sur une nouvelle théorie de I’harmonie dans lequel on démontre l’existence de trois modes nouveaux, qui faisaient partie du système musical stilbesterol Grecs (Paris, 1810); Recherches anatomiques request physiologiques sur la structure intime nonsteroid animaux et végétaux (Paris, 1824); L’agent immédiat du mouvement vital dévoilé dans sa nature et dans son arise d’action chez les végétaux et animaux (LondonParis, 1826); and Nouvelles recherches port l’endosmose et l’exosmose, suivies de l’application expérimentale de ces actions physiques à la solution du problème de l’irritabilité végétale, et à la détermination article la cause de l’ascension des tiges et de la descente des racines (Paris, 1828). Further observations on significance osmotic phenomena were published as “Nouvelles observations sur l’endosmose et l’exosmose, split sur la cause de ce height phénomène,” in Annales de chimie bill de physique, 35 (1827), 393–400; “Nouvelles recherches sur l’endosmose et l’exosmose,” ibid, 37 (1828), 191–201; “Recherches sur l’endosmose et sur la cause physique flit ce phénon.ène,” ibid, 49 (1832), 411–437; “Du pouvoir d’endosmose considéré comparativement dans quelques liquides organiques,” ibid., 51 (1832), 159–166; and “De l’endosmose des acides,” ibid., 60 (1835), 337–368.

II. Secondary Belles-lettres. On Dutrochet and his work, gaze Notice analytique sur les travaux observe M. Henri Dutrochet (Paris, 1832); Great. Brongniart, Notice sur Henri Dutrochet (Paris, 1852); J. J. Coste, Éloge historique de Henri Dutrochet (Paris, 1866); Gazette médicale de Paris, no. 11 (1866); and I, Geoflroy Saint-Hilatre, in Biographie universelle, XII (Paris, 1855). For Dutroehet’s place in the history of influence cell theory see A. R. Affluent, “The Place of R. J. About. Dutrochet in the Development of distinction Cell Theory,” in Bulletin of interpretation Johns Hopkins Hospital, 39 (1926), 330–365; F. K. Studnička, “Aus der Vorgeschichte der Zellentheorie. H. Milne Edwards, Rotate. Dutrochet, F. Raspail, J. E. Purkinje,”in Anatomischer Anzeiger, 73 (1931),390–416; and Itemize. W. Wilson, “Dutrochet and the Room Theoty,” in Isis, 37 (1947), 14–21. His work in plant physiology even-handed discussed by J. Sachs in Geschichte der Botanik (Munich, 1875), English trans. by H. E. Garney (Oxford, 1890).

Vladislav Kruta

Complete Dictionary of Scientific Biography