How does the countercurrent exchange system increase the efficiency of gas exchange between a fish’s gills and blood?

35 Your fish uses countercurrent exchange of gases in their respiratory organ. Explainthe countercurrent exchange and where it occurs, and what advantage it provides foryour fish. Answer in a sentence format.

(4a) A physoclistic fish is swimming toward the surface – what is happening inside its gas bladder while it is doing this? Be sure to explain fully the physiological changes that are taking place inside the fish at the level discussed in lecture. (4b) What will happen if the fish does not change the amount of gas in its gas bladder as it moves toward the surface?

Does salt water in any form when coming into contact with the human body affect the ability to swim?