Question

how do freshwater fishes and marine fishes carry out of regulation osmoregulation​

Answer 1

Answer:

The gills actively uptake salt from the environment by the use of mitochondria-rich cells. ... Some marine fish, like sharks, have adopted a different, efficient mechanism to conserve water, i.e., osmoregulation. They retain urea in their blood in relatively higher concentration.

Answer 2

Answer:

The gills actively uptake salt from the environment by the uses of mitochondria-rich cells. some marine fish like sharks, have adopted a different, efficient mechanism to conserve water.

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