Unlike Most Bony Fishes, Sharks Maintain Body Fluids That Are

Multiple Choice

Unlike most bony fishes, sharks maintain body fluids that are isoosmotic to seawater, so they are considered by many to be osmoconformers. Nonetheless, these sharks osmoregulate at least partially by ________.

A) using their gills and kidneys to rid themselves of sea salts
B) monitoring dehydration at the cellular level with special gated aquaporins
C) tolerating high urea concentrations that are balanced with internal salt concentrations to seawater osmolarity
D) synthesizing trimethylamine oxide, a chemical that binds and precipitates salts inside cells