Fermentation accounts for only a partial breakdown of glucose whereas in aerobic respiration it is completely degrated to `CO_(2)` and `H_(2)O`.

Answer

### Step-by-Step Text Solution:

1. **Understanding Fermentation and Aerobic Respiration**:
- Fermentation is a metabolic process that occurs in the absence of oxygen (anaerobic) and results in the partial breakdown of glucose.
- Aerobic respiration, on the other hand, occurs in the presence of oxygen and leads to the complete breakdown of glucose.

2. **Products of Each Process**:
- In fermentation, glucose is converted into products such as lactic acid or ethanol, depending on the type of fermentation (lactic acid fermentation or alcoholic fermentation).
- In aerobic respiration, glucose is fully oxidized to produce carbon dioxide (CO₂) and water (H₂O).

3. **Pathways Involved**:
- Aerobic respiration includes several key pathways:
- Glycolysis: The initial breakdown of glucose into pyruvate.
- Link Reaction: Conversion of pyruvate into acetyl-CoA.
- Krebs Cycle: A series of reactions that produce electron carriers and CO₂.
- Electron Transport Chain: The final stage where ATP is produced, and water is formed from oxygen and electrons.
- In contrast, fermentation only involves glycolysis followed by the conversion of pyruvate to either lactic acid or ethanol, without proceeding to the Krebs cycle or the electron transport chain.

4. **Energy Yield**:
- The energy yield from fermentation is significantly lower than that from aerobic respiration. This is because fermentation does not fully oxidize glucose, resulting in fewer ATP molecules being produced.
- Aerobic respiration is more efficient, yielding a higher amount of energy due to the complete oxidation of glucose to CO₂ and H₂O.

5. **Conclusion**:
- In summary, fermentation results in the partial breakdown of glucose, producing lactic acid or ethanol, while aerobic respiration completely degrades glucose to carbon dioxide and water, releasing more energy in the process.