7
GAS EXCHANGE I N FISH
D. I. RANDALL
I. Introduction . . . . . . . . .
11. Gas Exchange between Blood and Water . . .
A. Gas Exchange across the Gills
. . . .
B. Gas Exchange across the Skin . . . .
111. Gas Exchange between Blood and Tissues
. .
IV. Methods of Analysis of the Transfer of Gases
.
A. Introduction
. . . . . . . .
B. Transfer Factor
. . . . . . .
C. The Effectiveness of Gas Transfer
. . .
D. Capacity Rate Ratio
. . . . . .
E. Ventilation-Perfusion Ratio . . . . .
V. The Effects of Various Parameters on Gas Exchange
A. Temperature . , . . . . . .
B. Hypoxia . . . . . . . . .
C. Exercise . . . . . . . . .
References
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I. INTRODUCTION
Studies of gas exchange in fish have concentrated on the movement
of oxygen and carbon dioxide across the gills. In comparison the transfer
of gases between blood and tissues in fish has received very little attention except for a few special exchange sites that have been studied in
detail. These are the rete mirabile and gas gland of the teleost swim
bladder (see chapter by Steen, this volume) and, to a lesser extent, the
rete in the choroid layer of the eye of teleosts (Wittenberg and Wittenberg, 1962).
Fish breathe either seawater, freshwater, or air or some combination of
these media, There are a number of surfaces in fish for the exchange of
gases between blood and the medium. The primary site, the gills, is
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