Which one of the follwoing statements is incorrect
| A. |
The principle of coutercurrent flow facilitates efficeint respiration in gills of fishes |
| B. |
The residual air in lungs slightly decreases the defficiency of respiration in mammals |
| C. |
The presence of non-respiratory air sacs, increases the efficiency of respiration in birds |
| D. |
In insects, circulating body fluids serve to distribute oxygen to tissues |
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