How we will describe the whole mechanism of fish breathing under water? How they absorb oxygen and and then remove oxygen through a process known as gas exchange?


closed as off-topic by David, Bryan Krause, theforestecologist, kmm, fileunderwater Nov 14 '18 at 14:02

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Homework questions are off-topic on Biology unless you have shown your attempt at an answer. For more information see our homework policy." – Bryan Krause, theforestecologist, kmm
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 3
    $\begingroup$ Did you read articles like this about respiration in fish already? If so, could you please edit your post and add, what exactly remained unclear? $\endgroup$ – Arsak Nov 13 '18 at 13:54

Fish are able to obtain oxygen that is dissolved within the water, and exchange it along with Carbon Dioxide through their gill structure, called filaments. The gills are located adjacent to the mouth and filaments include a large amount of blood vessels. Those blood vessels (capillaries) are close to the gill filament surface and move in the opposite direction to the water flow, which they are exposed to by means of the fish drawing in water through it's mouth. The tissue that comprises the filament is porous and allows for diffusion of these small molecules (oxygen and carbon dioxide) across this tissue and into the blood vessels. Each red blood vessel consists of four "Heme groups," which are designed exclusively to bind to oxygen and transport it through the body. A process called the Root effect (Bohr effect in other vertebrates) in hemoglobin regulates the "drop-off" of oxygen by recognition of low pH values.

Hughes, G. M., & Morgan, M. (1973). The structure of fish gills in relation to their respiratory function. Biological reviews, 48(3), 419-475.

Bonaventura, C. E. L. I. A., Sullivan, B., & Bonaventura, J. (1976). Spot hemoglobin. Studies on the Root effect hemoglobin of a marine teleost. Journal of Biological Chemistry, 251(7), 1871-1876.


Not the answer you're looking for? Browse other questions tagged or ask your own question.