The maximum usable energy per molecule of glucose metabolised will be generated during

Options

A. Aerobic respiration by germinating seeds
B. Production of methanol by enteric bacteria
C. Fermentation into ethanol by yeast
D. Glycolysis in the skeletal muscle of a sprinter performing a hundred metre dash

Answer

To determine the maximum usable energy per molecule of glucose metabolized, we need to analyze the different processes of glucose metabolism mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Types of Respiration**:
- There are two main types of respiration: aerobic and anaerobic.
- Aerobic respiration occurs in the presence of oxygen, while anaerobic respiration occurs in the absence of oxygen.

2. **Understand the Energy Yield**:
- In aerobic respiration, glucose is completely oxidized, yielding a high amount of energy.
- In anaerobic respiration, glucose is only partially oxidized, resulting in a lower energy yield.

3. **Analyze Each Option**:
- **Option A: Aerobic respiration by germinating seeds**: This process involves complete oxidation of glucose, leading to a net gain of approximately 38 ATP molecules per glucose molecule.
- **Option B: Production of methanol by enteric bacteria**: This is an anaerobic process, yielding only about 2 ATP molecules.
- **Option C: Fermentation into ethanol by yeast**: This is also an anaerobic process, yielding about 2 ATP molecules.
- **Option D: Glycolysis in the skeletal muscles of a sprinter**: Glycolysis is the first step in both aerobic and anaerobic respiration and yields only 2 ATP molecules.

4. **Conclusion**:
- Among all the options, aerobic respiration by germinating seeds produces the maximum usable energy, yielding 38 ATP molecules.
- Therefore, the answer is **A: Aerobic respiration by germinating seeds**.