African lungfish, which are often found in small, stagnant pools of fresh water, produce urea as a nitrogenous waste. What is the advantage of this adaptation?
A) Urea takes less energy to synthesize than ammonia.
B) Small, stagnant pools do not provide enough water to dilute the toxic ammonia.
C) The highly toxic urea makes the pool uninhabitable to potential competitors.
D) Urea makes lungfish tissue hypoosmotic to the pool.

Question

Quizplus · Accepted Answer

Small, stagnant pools do not provide enough water to dilute the toxic ammonia. Urea is less toxic and can be excreted at a higher concentration than ammonia, making it an effective adaptation for organisms living in such environments.

African Lungfish, Which Are Often Found in Small, Stagnant Pools