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Home > Dictionary of Science Quotations > Scientist Names Index S > Theodor Schwann Quotes

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Theodor Schwann
(7 Dec 1810 - 11 Jan 1882)

German physiologist.


Science Quotes by Theodor Schwann (5 quotes)

The cause of nutrition and growth resides not in the organism as a whole but in the separate elementary parts—the cells.
— Theodor Schwann
Mikroskopische Untersuchungen über die Uebereinstimmung in der Struktur und dem Wachsthum der Thiere und Pflanzen (1839). Microscopic Researches into the Accordance in the Structure and Growth of Animals and Plants, trans. Henry Smith (1847), 192.
Science quotes on:  |  Cell (90)  |  Elementary (11)  |  Growth (70)  |  Nutrition (11)  |  Organism (70)  |  Part (55)  |  Reside (4)

The elementary parts of all tissues are formed of cells in an analogous, though very diversified manner, so that it may be asserted, that there is one universal principle of development for the elementary parts of organisms, however different, and that this principle is the formation of cells.
— Theodor Schwann
Mikroskopische Untersuchungen über die Uebereinstimmung in der Struktur und dem Wachsthum der Thiere und Pflanzen (1839). Microscopic Researches into the Accordance in the Structure and Growth of Animals and Plants, trans. Henry Smith (1847), 165.
Science quotes on:  |  Analogy (26)  |  Assertion (16)  |  Cell (90)  |  Development (122)  |  Difference (135)  |  Diversity (32)  |  Elementary (11)  |  Formation (34)  |  Manner (11)  |  Organism (70)  |  Principle (97)  |  Tissue (15)  |  Universality (9)

The fibrous material and muscle were thus digested in the same way as the coagulated egg albumen, namely, by free acid in combination with another substance active in very small amounts. Since the latter really carries on the digestion of the most important animal nutrient materials, one might with justice apply to it the name pepsin.
— Theodor Schwann
'Ueber das Wesen des Verdauungsprocesses', Archiv für Anatomie, Physiologie und Wissenschaftliche Medicin (1836), 90-138. Trans. L. G. Wilson, 'The Discovery of Pepsin', in John F. Fulton and Leonard G. Wilson (eds.), Selected Readings in the History of Physiology (1966), 191.
Science quotes on:  |  Acid (14)  |  Albumen (2)  |  Coagulation (3)  |  Digestion (15)  |  Egg (27)  |  Fibre (5)  |  Muscle (24)  |  Nutrient (2)

The principal result of my investigation is that a uniform developmental principle controls the individual elementary units of all organisms, analogous to the finding that crystals are formed by the same laws in spite of the diversity of their forms.
— Theodor Schwann
Mikroskopische Untersuchungen über die Uebereinstimmung in der Struktur und dem Wachsthum der Thiue und Pflanzen (1839). Microscopic Researches into the Accordance in the Structure and Growth of Animals and Plants, trans. Henry Smith (1847), 1.
Science quotes on:  |  Analogy (26)  |  Control (41)  |  Crystal (22)  |  Development (122)  |  Diversity (32)  |  Elementary (11)  |  Form (70)  |  Formation (34)  |  Individual (59)  |  Investigation (83)  |  Law (273)  |  Organism (70)  |  Result (129)  |  Uniform (5)  |  Unit (15)

We set out, therefore, with the supposition that an organised body is not produced by a fundamental power which is guided in its operation by a definite idea, but is developed, according to blind laws of necessity, by powers which, like those of inorganic nature, are established by the very existence of matter. As the elementary materials of organic nature are not different from those of the inorganic kingdom, the source of the organic phenomena can only reside in another combination of these materials, whether it be in a peculiar mode of union of the elementary atoms to form atoms of the second order, or in the arrangement of these conglomerate molecules when forming either the separate morphological elementary parts of organisms, or an entire organism.
— Theodor Schwann
Mikroskopische Untersuchungen über die Uebereinstimmung in der Struktur und dem Wachsthum der Thiere und Pflanzen (1839). Microscopic Researches into the Accordance in the Structure and Growth of Animals and Plants, trans. Henry Smith (1847), 190-1.
Science quotes on:  |  Arrangement (25)  |  Atom (164)  |  Blind (8)  |  Combination (37)  |  Definite (5)  |  Development (122)  |  Difference (135)  |  Elementary (11)  |  Fundamental (59)  |  Idea (226)  |  Inorganic (5)  |  Kingdom (18)  |  Law (273)  |  Material (60)  |  Molecule (82)  |  Morphology (11)  |  Nature (534)  |  Necessity (78)  |  Operation (53)  |  Organic (19)  |  Organism (70)  |  Organization (51)  |  Phenomenon (114)  |  Power (103)  |  Supposition (25)  |  Union (6)



Quotes by others about Theodor Schwann (2)

The history of the knowledge of the phenomena of life and of the organized world can be divided into two main periods. For a long time anatomy, and particularly the anatomy of the human body, was the a and ? of scientific knowledge. Further progress only became possible with the discovery of the microscope. A long time had yet to pass until through Schwann the cell was established as the final biological unit. It would mean bringing coals to Newcastle were I to describe here the immeasurable progress which biology in all its branches owes to the introduction of this concept of the cell. For this concept is the axis around which the whole of the modem science of life revolves.
'Partial Cell Functions', Nobel Lecture, 11 Dec 1908. In Nobel Lectures: Physiology or Medicine 1901-1921 (1967), 304.
Science quotes on:  |  Anatomy (32)  |  Cell (90)  |  Microscope (47)

The extracellular genesis of cells in animals seemed to me, ever since the publication of the cell theory [of Schwann], just as unlikely as the spontaneous generation of organisms. These doubts produced my observations on the multiplication of blood cells by division in bird and mammalian embryos and on the division of muscle bundles in frog larvae. Since then I have continued these observations in frog larvae, where it is possible to follow the history of tissues back to segmentation.
'Ueber extracellulare Eutstehung thierischer Zelleu und όόber Vermehrung derselben durch Theilung', Archiv fόr Anatomie, Physiologie und Wissenschaftliche Medicin (1852), 1, 49-50. Quoted in Erwin H. Ackerknecht, Rudolf Virchow: Doctor Statesman Anthropologist (1953), 83-4.
Science quotes on:  |  Animals (2)  |  Bird (57)  |  Blood (63)  |  Bundle (4)  |  Cell (90)  |  Continuation (13)  |  Division (19)  |  Doubt (67)  |  Embryo (15)  |  Frog (24)  |  Generation (56)  |  Genesis (10)  |  History (156)  |  Larva (4)  |  Mammal (17)  |  Multiplication (11)  |  Muscle (24)  |  Observation (264)  |  Organism (70)  |  Publication (75)  |  Segmentation (2)  |  Spontaneity (4)  |  Theory (353)  |  Tissue (15)


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  • todayinsci icon 7 Dec - short biography, births, deaths and events on date of Schwann's birth.

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