Conversion of urea to `CO_2` and ammonia is done by

Options

A. Pepsin
B. Urease
C. Lactase
D. Nuclease

Answer

To solve the question regarding the conversion of urea to carbon dioxide and ammonia, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: The question asks about the conversion of urea (NH2CO) to carbon dioxide (CO2) and ammonia (NH3). This reaction involves hydrolysis, which is the addition of water to break down a compound.

2. **Determine the Enzyme Involved**: The enzyme responsible for catalyzing the hydrolysis of urea is known as urease. Urease facilitates the breakdown of urea into carbon dioxide and ammonia.

3. **Write the Reaction**: The chemical reaction can be represented as:
\[ \text{Urea (NH}_2\text{CO)} + \text{H}_2\text{O} \xrightarrow{\text{urease}} \text{CO}_2 + \text{NH}_3 \]
This indicates that urea reacts with water in the presence of urease to produce carbon dioxide and ammonia.

4. **Consider the Temperature**: The reaction occurs at a temperature of about 145 degrees Celsius, indicating that it is an endothermic reaction, meaning it absorbs heat.

5. **Eliminate Incorrect Options**:
- **Pepsin**: This enzyme digests proteins, not urea.
- **Lactase**: This enzyme breaks down lactose, not urea.
- **Nuclease**: This enzyme cleaves nucleic acids, not urea.

6. **Select the Correct Option**: Based on the information, the enzyme that converts urea to carbon dioxide and ammonia is urease. Therefore, the correct answer is option B: urease.

### Final Answer:
The conversion of urea to carbon dioxide and ammonia is done by **urease**.

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