Glycolysis is

Options

A. `C_(6)H_(12)O_(6)+6O_(2)rarr6CO_(2)+6H_(2)O`
B. `C_(6)H_(12)O_(6)rarr2C_(2)H_(5)OH+2CO_(2)`
C. `C_(6)H_(12)O_(6)rarr2C_(3)H_(4)O_(3)+4H^(+)`
D. `C_(3)H_(4)O_(3)+NADHrarrC_(2)H_(5)OH+CO_(2)+NAD^(+)`

Answer

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

1. **Understanding Glycolysis**: Glycolysis is the metabolic pathway that converts glucose (C6H12O6) into pyruvate (C3H4O3), producing a small amount of ATP and NADH in the process. It occurs in the cytoplasm of cells and does not require oxygen, making it an anaerobic process.

2. **Evaluating the Options**:
- **Option 1**: C6H12O6 + 6O2 → 6CO2 + 6H2O
- This reaction represents the complete oxidation of glucose, which is part of aerobic respiration (including glycolysis, Krebs cycle, and electron transport chain). Therefore, this is not glycolysis.

- **Option 2**: C6H12O6 → 2C2H5OH + 2CO2
- This reaction describes fermentation, where glucose is converted into ethanol and carbon dioxide in the absence of oxygen. This process includes glycolysis but is not glycolysis itself. Hence, this option is incorrect.

- **Option 3**: C6H12O6 → 2C3H4O3 + 4H+
- Here, glucose is converted into two molecules of pyruvic acid (C3H4O3), which is the direct outcome of glycolysis. This option correctly represents glycolysis.

- **Option 4**: C3H4O3 + NADH → C2H5OH + CO2 + NAD+
- This reaction describes the conversion of pyruvate to ethanol, which is part of fermentation. It does not represent glycolysis directly, making this option incorrect.

3. **Conclusion**: Based on the evaluation of the options, Option 3 is the correct representation of glycolysis, as it shows the conversion of glucose into pyruvic acid.

**Final Answer**: Glycolysis is represented by the reaction: C6H12O6 → 2C3H4O3 + 4H+ (Option 3).

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