Oxalosuccinic acid, a transient intermediary compound of Krebs cycle is

Options

A. 4-carbon compound
B. 5-carbon compound
C. 6-carbon compound
D. 3-carbon compound.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about oxalosuccinic acid, specifically its classification as a transient intermediary compound in the Krebs cycle.

2. **Identifying the Source Compound**: Oxalosuccinic acid is formed from isocitrate, which is a known 6-carbon compound.

3. **Reaction Process**: The transformation occurs during the fourth step of the Krebs cycle. In this step, isocitrate undergoes a reaction where a pair of hydrogen atoms is removed.

4. **Enzyme Involvement**: The enzyme responsible for this reaction is isocitrate dehydrogenase. This enzyme catalyzes the conversion of isocitrate to oxalosuccinic acid.

5. **Carbon Count**: Since oxalosuccinic acid is derived from isocitrate (a 6-carbon compound), it retains the same number of carbon atoms. Therefore, oxalosuccinic acid is also a 6-carbon compound.

6. **Conclusion**: Based on the above steps, we conclude that oxalosuccinic acid is classified as a 6-carbon compound.

**Final Answer**: Oxalosuccinic acid is a 6-carbon compound.

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