Question

Which animal was not Uricotelic?

• A. Birds
• B. Land snail
• C. Reptiles
• D. Adult Frog

Hint:

An easy way to remember the excretory products based on habitat:
Aquatic (fish, tadpoles) $\rightarrow$ Ammonotelic.
Terrestrial/Semi-aquatic (mammals, adult frogs) $\rightarrow$ Ureotelic.
Highly dry-adapted/Aerial (birds, reptiles, snails) $\rightarrow$ Uricotelic.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks to identify the animal among the given options that is NOT uricotelic.
Uricotelic animals are those that excrete nitrogenous waste primarily in the form of uric acid.

Step 2: Key Formula or Approach:
We analyze the mode of excretion of different animal groups based on water conservation needs.
Animals are classified into three major groups:
1. Ammonotelic (excrete ammonia, requires high water).
2. Ureotelic (excrete urea, requires moderate water).
3. Uricotelic (excrete uric acid, requires minimal water).

Step 3: Detailed Explanation:

• Uricotelic organisms excrete uric acid or its salts as a paste or dry pellet.

• Uric acid is highly insoluble in water and relatively non-toxic, allowing organisms to conserve maximum body water.

• This is a vital adaptation for terrestrial environments with limited water availability, such as those inhabited by birds, land snails, insects, and reptiles.

• Consequently, birds, land snails, and reptiles are classically categorized as uricotelic.

• On the other hand, the adult frog is a semi-aquatic amphibian.

• Adult frogs live in environments where water is accessible, and they excrete their nitrogenous waste as urea, which is soluble in water and moderately toxic.

• Thus, adult frogs are ureotelic, not uricotelic.

• Note that the larval stage of a frog (tadpole) is ammonotelic because it lives exclusively in water.


Step 4: Final Answer:
The adult frog is ureotelic, making it the correct option for an animal that is not uricotelic.