Vertebrates face many physiological challenges with relation

Vertebrates face many physiological challenges with relation to osmotic pressure. What is a possible challenge freshwater fishes face as a result of their osmoregulatory mechanisms? (Choose One)

A. These fishes tend to accumulate high amount of salts internally due to the small amount of urine excreted.
B. These fish would be subject to shriveling due to the loss of water through their gills into the environment.
C. These fish would be subject to swelling by movement of water into the bodies.
D. Freshwater fish are osmoconformers yet still have to regulate the intake and excretion of ions.

Solution

The gills of freashwater fishes are involve in actively taking the salt from the environment by the use of mitochondria-rich cells. Water will diffuse into the fish therefore it excretes a very hypotonic or diluted urine to releas all the excess water.therfore option C. These fish would be subject to swelling by movement of water into the bodies is correct