Sharks and Rays Deal with the Osmotic Stress of Living

question 10

Multiple Choice

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

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Definitions:

Nonexcludable

A characteristic of a good or service where it is impossible to prevent individuals from enjoying its benefits once it is provided.

Marginal Social Cost

The additional cost to society as a whole from producing one extra unit of a good or service, including both private costs and externalities.

Rival

A competitor or adversary who is in competition for the same objective or for superiority in the same field.

Excludable

Describes a good or service for which it is possible to prevent non-paying customers from accessing it.