Question: unlike marine members of actinopterygii rayfinned fish members of chondrichthyes...
Unlike marine members of Actinopterygii (ray-finned fish), members of Chondrichthyes (sharks and rays) maintain their salt-water balance by?
active transport in the gills to retain water
tolerating high concentrations of sodium and other ions in the blood and tissues
tolerating high concentrations of urea in their blood and tissues.
active transport in the kidneys to excrete salts