Choose the wrong statement..

Options

A. In ureotelic organisms, ammonia is not a product of metabolism.
B. In mammals some amount of urea may be retained in the kidney matrix of ureotelics to maintain osmolarity.
C. In fishes, kidneys do not play any significant role in the removal of ammonium ions.
D. Urea and uric acid are less toxic than ammonia.

Answer

To solve the question, we need to identify the wrong statement among the given options. Let's analyze each option step by step.

### Step 1: Analyze Option 1
- **Statement**: In ureotallic organisms, ammonia is not a product of metabolism.
- **Analysis**: Ureotallic organisms do produce ammonia as a byproduct of protein metabolism. However, they convert ammonia into urea for excretion to reduce toxicity and water loss. Therefore, this statement is incorrect.

### Step 2: Analyze Option 2
- **Statement**: In mammals, some amount of urea may be retained in the kidney matrix of ureotallic organisms to maintain osmolarity.
- **Analysis**: This statement is true. Urea can be retained in the kidneys to help regulate osmolarity and maintain fluid balance.

### Step 3: Analyze Option 3
- **Statement**: In fishes, kidneys do not play any significant role in the removal of ammonium ions.
- **Analysis**: This statement is also true. Most fish excrete ammonia directly into the water through their gills, and their kidneys are not primarily responsible for excreting ammonium ions.

### Step 4: Analyze Option 4
- **Statement**: Urea and uric acid are less toxic than ammonia.
- **Analysis**: This statement is correct. Urea and uric acid are less toxic than ammonia and require less water for excretion, making them more suitable for organisms that need to conserve water.

### Conclusion
After analyzing all the options, we find that the wrong statement is **Option 1**: "In ureotallic organisms, ammonia is not a product of metabolism."

### Final Answer
The wrong statement is **Option 1**.

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