Sharks and rays deal with the osmotic stress of living in seawater mainly by ____.
A) active transport of ions into the body through the gills
B) excreting nitrogenous wastes through their kidneys as urea
C) active transport of ions out of the body by chloride cells
D) excreting excess salt through the actions of specialized salt glands in their heads
E) maintaining high levels of urea and trimethylamine oxide in body fluids

Question

Quizplus · Accepted Answer

Sharks and rays primarily manage the osmotic stress of living in seawater by maintaining high levels of urea and trimethylamine oxide in their body fluids. This adaptation allows them to be osmoconformers, where the osmolarity of their body fluids matches that of the surrounding seawater, reducing the osmotic stress.

Sharks and Rays Deal with the Osmotic Stress of Living