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The effects of acids on a soil nematode

Published online by Cambridge University Press:  06 April 2009

William Stephenson
Affiliation:
Department of Zoology, The University, Bristol

Extract

1. The effects of the following acids were studied: hydrochloric, nitric, sulphuric, formic, acetic, propionic, butyric, isovaleric, glycollic, lactic, oxalic, malonic, succinic, malic, tartaric, and citric.

2. The general effects of immersion in acid media include an increased stickiness of the cuticle in certain solutions, and the development of lateral bulges in the cuticle at the anterior region of the body, not necessarily in the same solutions. Movement gradually decreases, and death eventually occurs, often followed by swelling.

3. The survival times in various solutions were noted. Preliminary experiments showed that the logarithm of the survival time was approximately proportional to the logarithm of the normality of the acid. Later results showed great variability, and it was necessary to restrict the work to a single normality of each acid.

4. The toxicities of 0·206 N solutions of the sixteen acids were measured. These results showed that the mineral acids had markedly greater effects than the organic acids, and the importance of the former was further illustrated by using mixtures of HCl containing varying amounts of organic acids. The differences between the mineral acids may be explained by the lyotropic effects of the anions.

5. Equal normalities of organic acids were made up in a solution of HCl sufficiently strong to render the organic acids almost entirely undissociated. The relative toxicities of the mixtures were essentially the same as those of the dissociated acids.

6. The differences between the acids are thus partly due to the pH differences, and partly due to the dissimilar effects of the undissociated acids. The latter are believed to be due to a variety of causes, including molecular size, polarity of the molecule, and other factors as yet undecided.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1945

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References

REFERENCES

Bělehrádek, J. & Sohwarz, F. (1928). Bull. Soc. Chim. biol., Paris, 10, 909.Google Scholar
von Brand, T. (1934). Ergebn. Biol. 10, 37.Google Scholar
Crozier, W. J. (1916). J. Biol. Chem. 24, 255.CrossRefGoogle Scholar
Davson, H. & Danielli, J. F. (1943). The Permeability of Natural Membranes. Cambridge.Google Scholar
Flury, F.(1912). Arch. Exp. Path. Pharmak. 67, 275.CrossRefGoogle Scholar
Fuhner, H. & Neubauer, E. (1907). Arch. Exp. Path. 56, 333.CrossRefGoogle Scholar
Harvey, E. N. (1914). Int. Z. phys.-chem. Biol. 1, 463.Google Scholar
Jacques, A. G. (1936). J. Gen. Physiol. 19, 397.CrossRefGoogle Scholar
Lillie, R. S. (1927). J. Gen. Physiol. 8, 339.CrossRefGoogle Scholar
Lloyd, D. J. & Shore, A. (1938). The Chemistry of the Proteins. London.Google Scholar
Loeb, J. (1913). Artificial Pathenogenesis and Fertilization. Chicago.Google Scholar
Marklund, G. (1936). Acta bot. Fenn. 18, 5.Google Scholar
McBain, J. W.(1932). The Sorption of Gases and Vapours by Solids. London.Google Scholar
Michaelis, L. (1926). Hydrogen-ion Concentration, 1. London.Google Scholar
Osterhout, W. J. V. (1925). J. Gen. Physiol. 8, 131.CrossRefGoogle Scholar
Osterhout, W. J. V. & Dorcas, M. J. (1925). J. Gen. Physiol. 9, 255.CrossRefGoogle Scholar
Paul, T. (1922). Z. Electrochem. 28, 435.Google Scholar
Ruhland, W. & Hoffmann, C. (1925). Planta, 1, 1.CrossRefGoogle Scholar
Slater, W. K. (1928). Biol. Rev. 3, 303.CrossRefGoogle Scholar
Snedecor, G. W. (1938). Statistical Methods. Ames, Iowa.Google Scholar
Stephenson, W. (1942 a). Parasitology, 34, 246.CrossRefGoogle Scholar
Stephenson, W. (1942 b). Parasitology, 34, 253.CrossRefGoogle Scholar
Stephenson, W. (1943). Parasitology, 35, 167.CrossRefGoogle Scholar
Stoklasa, J. J. (1933). Publ. Fac. Méd. Brno, 12, 131.Google Scholar
Taylor, N. W. (1928). J. Gen. Physiol. 11, 207.CrossRefGoogle Scholar
Weinland, E. (1904). Z. Biol. 45, 113.Google Scholar
Yonge, C. M. (1936). Proc. Roy. Soc. B, 120, 15.Google Scholar