Hexose monophosphate shunt is

Options

A. Pentose phosphate pathway or a set of reactions that bypasses the glycolysis and Krebs cycle routes for glucose oxidation in the cell.
B. Conversion of glucose into pyruvic acid.
C. The sum of all chemical transformations.
D. The process by which starch is synthesized.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Hexose Monophosphate Shunt**: The Hexose Monophosphate Shunt (HMP) is also referred to as the Pentose Phosphate Pathway (PPP). It is a metabolic pathway that operates alongside glycolysis.

2. **Identifying the Purpose of the HMP**: The primary function of the HMP is to generate NADPH and ribose-5-phosphate. NADPH is essential for various biosynthetic reactions, while ribose-5-phosphate is crucial for the synthesis of nucleic acids.

3. **Location of the Pathway**: The HMP occurs in the cytoplasm of the cell. It is important to note that it runs parallel to glycolysis, meaning it provides an alternative route for glucose metabolism.

4. **Comparison with Other Pathways**:
- **Glycolysis**: This pathway converts glucose into pyruvic acid and is not the same as the HMP.
- **Metabolism**: This term encompasses all chemical transformations in the cell, which is broader than the HMP.
- **Starch Synthesis**: This occurs during photosynthesis and is unrelated to the HMP.

5. **Key Sites for HMP Activity**: The major sites for the Hexose Monophosphate Shunt are the red blood cells (RBCs) and the liver, where the demand for NADPH and ribose-5-phosphate is high.

6. **Conclusion**: Given the options provided, the correct answer is that the Hexose Monophosphate Shunt is synonymous with the Pentose Phosphate Pathway, which is a set of reactions that bypasses glycolysis and the Krebs cycle for glucose oxidation.

**Final Answer**: The Hexose Monophosphate Shunt is also known as the Pentose Phosphate Pathway.

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