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THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH

1. Reasons are given for believing that the uptake of Na(+), Cl(-), and NaCl by the crayfish occurs through the gills. 2. A crayfish in fresh water, with a Cl concentration of about 0.2 mEq./l., can) by active Cl absorption, compensate entirely for Cl lost in the urine. 3. The carbonic anhydrase act...

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Autor principal: Maluf, N. S. Rustum
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1940
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2142017/
https://www.ncbi.nlm.nih.gov/pubmed/19873206
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author Maluf, N. S. Rustum
author_facet Maluf, N. S. Rustum
author_sort Maluf, N. S. Rustum
collection PubMed
description 1. Reasons are given for believing that the uptake of Na(+), Cl(-), and NaCl by the crayfish occurs through the gills. 2. A crayfish in fresh water, with a Cl concentration of about 0.2 mEq./l., can) by active Cl absorption, compensate entirely for Cl lost in the urine. 3. The carbonic anhydrase activity of the gills is markedly higher than that of other tissues of the crayfish, but the equivalent CO(2) output of the crayfish is far in excess of the equivalent Cl absorption per unit time and weight and thus fails to warrant the supposition that Cl absorption is of respiratory importance. 4. The carbonic anhydrase activity of the soft integument of the lobster, before and after molting, and of the hypodermis of the hard-cuticled animal is almost identical and of the same order as that of other tissues of the lobster. 5. The concentration of the electrolytes was about 7.5 mEq./l.; i.e., considerably lower than in the blood of the crayfish. Cl(-) can be taken up independently of the complementary cation. Na(+) can be taken up independently of the complementary anion. K(+) and SO(4) (=) are not taken up at all. In pure NaCl, the Na(+) and Cl(-) are absorbed evidently largely together. Ca(++) is absorbed only in newly molted animals and in animals preparing to molt but is not absorbed by hard-cuticled animals not preparing to molt. Ca(++) is taken up independently of Cl(-) in pure CaCl(2). 6. Newly molted animals absorb Ca(++) at a rate exceeding that of the absorption of other absorbable ions (Na(+) and Cl(-)) in the same equivalent concentration. 7. A crayfish utilizes the Ca(++) in fresh water in the calcification of its cuticle. Since the animal does not swallow water, the Ca(++) must enter through the exterior. Reasons are given for believing that, unlike Na(+) and Cl(-), Ca(++) is absorbed directly from the exterior by the integument and does not enter the body through the gills. 8. During molting, only about 4 per cent of the raw ash and 2.3 per cent of the organic material of the old cuticle is resorbed.
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spelling pubmed-21420172008-04-23 THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH Maluf, N. S. Rustum J Gen Physiol Article 1. Reasons are given for believing that the uptake of Na(+), Cl(-), and NaCl by the crayfish occurs through the gills. 2. A crayfish in fresh water, with a Cl concentration of about 0.2 mEq./l., can) by active Cl absorption, compensate entirely for Cl lost in the urine. 3. The carbonic anhydrase activity of the gills is markedly higher than that of other tissues of the crayfish, but the equivalent CO(2) output of the crayfish is far in excess of the equivalent Cl absorption per unit time and weight and thus fails to warrant the supposition that Cl absorption is of respiratory importance. 4. The carbonic anhydrase activity of the soft integument of the lobster, before and after molting, and of the hypodermis of the hard-cuticled animal is almost identical and of the same order as that of other tissues of the lobster. 5. The concentration of the electrolytes was about 7.5 mEq./l.; i.e., considerably lower than in the blood of the crayfish. Cl(-) can be taken up independently of the complementary cation. Na(+) can be taken up independently of the complementary anion. K(+) and SO(4) (=) are not taken up at all. In pure NaCl, the Na(+) and Cl(-) are absorbed evidently largely together. Ca(++) is absorbed only in newly molted animals and in animals preparing to molt but is not absorbed by hard-cuticled animals not preparing to molt. Ca(++) is taken up independently of Cl(-) in pure CaCl(2). 6. Newly molted animals absorb Ca(++) at a rate exceeding that of the absorption of other absorbable ions (Na(+) and Cl(-)) in the same equivalent concentration. 7. A crayfish utilizes the Ca(++) in fresh water in the calcification of its cuticle. Since the animal does not swallow water, the Ca(++) must enter through the exterior. Reasons are given for believing that, unlike Na(+) and Cl(-), Ca(++) is absorbed directly from the exterior by the integument and does not enter the body through the gills. 8. During molting, only about 4 per cent of the raw ash and 2.3 per cent of the organic material of the old cuticle is resorbed. The Rockefeller University Press 1940-11-20 /pmc/articles/PMC2142017/ /pubmed/19873206 Text en Copyright © Copyright, 1940, by The Rockefeller Institute for Medical Research This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Article
Maluf, N. S. Rustum
THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title_full THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title_fullStr THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title_full_unstemmed THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title_short THE UPTAKE OF INORGANIC ELECTROLYTES BY THE CRAYFISH
title_sort uptake of inorganic electrolytes by the crayfish
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2142017/
https://www.ncbi.nlm.nih.gov/pubmed/19873206
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