Biological oxidation of respiratory substrate causes

Options

A. Gain of oxygen
B. Gain of hydrogen
C. Loss of oxygen
D. Loss of hydrogen.

Answer

**Step-by-Step Solution:**

1. **Understanding Biological Oxidation**: Biological oxidation refers to the metabolic processes that cells use to convert nutrients into energy. This process is a key part of cellular respiration.

2. **Energy Release**: During the biological oxidation of respiratory substrates (like glucose), energy is released. This energy is primarily used by cells to perform various functions.

3. **Forms of Energy**: The energy released during respiration is not only in the form of heat but is also captured in the form of ATP (adenosine triphosphate). ATP serves as the energy currency of the cell, powering various cellular activities.

4. **Oxidation Process**: The term "oxidation" indicates a chemical process where a substance loses electrons or hydrogen. In the context of respiration, this means that the respiratory substrates lose hydrogen atoms.

5. **Role of NADH and FADH2**: During respiration, electron carriers such as NADH and FADH2 are produced. These molecules play a crucial role in transferring electrons to the electron transport chain, ultimately leading to the production of ATP.

6. **Final Outcome**: The overall outcome of biological oxidation is the loss of hydrogen from the respiratory substrates, which facilitates the release of energy and the formation of ATP.

7. **Conclusion**: Therefore, the biological oxidation of respiratory substrates causes a loss of hydrogen, which is essential for energy production in cells.

**Correct Answer**: The biological oxidation of respiratory substrates causes a loss of hydrogen.

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