Ornithine cycle performs

Options

A. ATP synthesis
B. Urea formation in spleen
C. Urea formation in liver
D. Urine formation in liver

Answer

### Step-by-Step Solution:

1. **Understanding the Ornithine Cycle**:
- The Ornithine Cycle is also known as the Urea Cycle. It is a series of biochemical reactions that convert ammonia, which is toxic, into urea, which is less toxic and can be excreted from the body.

2. **Purpose of the Urea Cycle**:
- The main purpose of the Urea Cycle is to detoxify ammonia produced during the metabolism of nitrogen-containing compounds. Ammonia is a byproduct of protein metabolism and is highly toxic to cells.

3. **Chemical Composition of Urea**:
- Urea has the chemical formula NH2CO(NH2), indicating that it is formed from two molecules of ammonia (NH3) and one molecule of carbon dioxide (CO2).

4. **Location of the Urea Cycle**:
- The Urea Cycle takes place primarily in the liver. It occurs in two locations within liver cells:
- The mitochondrial matrix (where some steps of the cycle occur).
- The cytoplasm (where the remaining steps of the cycle occur).

5. **Identifying the Correct Answer**:
- The question asks what the Ornithine Cycle performs. The options provided include:
- A) Synthesis (not related to Urea Cycle)
- B) Urea formation in spleen (incorrect, as the spleen is not involved in urea formation)
- C) Urea formation in liver (correct, as the Urea Cycle occurs in the liver)
- D) Urein formation in liver (incorrect, as Urein is formed in the kidneys)
- Therefore, the correct answer is option C: Urea formation in the liver.