In ornithine cycle, enzyme arginase breaks down arginine into

Options

A. Citrulline and ammonia
B. Ornithine and ammonia
C. Ornithine and urea
D. Citruline and urea

Answer

**Step-by-Step Solution:**

1. **Understanding the Ornithine Cycle**: The Ornithine cycle, also known as the urea cycle, is a series of biochemical reactions that occur in the liver. Its primary purpose is to convert ammonia, which is toxic, into urea, which can be excreted from the body.

2. **Role of Arginine**: Arginine is an amino acid that plays a crucial role in the urea cycle. It is one of the key substrates in the cycle.

3. **Enzyme Involvement**: The enzyme arginase is specifically involved in the breakdown of arginine. Enzymes are biological catalysts that speed up chemical reactions in the body.

4. **Reaction Catalyzed by Arginase**: The enzyme arginase catalyzes the hydrolysis of arginine. This reaction results in the production of two products: urea and ornithine.

5. **Final Answer**: Therefore, in the ornithine cycle, the enzyme arginase breaks down arginine into urea and ornithine.

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