Assertion :- In cellular respiration, ETS electron movement is a downhill journey.
Reason :- Electrons move from high redox potential to low redox potential to low redox potential.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.
C. If Assertion is false, but Reason is true
D. If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that in cellular respiration, the electron transport system (ETS) involves electron movement that is described as a "downhill journey." This implies that the electrons are moving from a state of higher energy to lower energy.

2. **Understanding the Reason:**
- The reason provided states that electrons move from high redox potential to low redox potential. Redox potential refers to the tendency of a chemical species to acquire electrons and thereby be reduced. A higher redox potential indicates a greater ability to attract electrons.

3. **Connecting Assertion and Reason:**
- In the context of the ETS, electrons are transferred through a series of protein complexes. As they move through these complexes, they go from a less electronegative (higher redox potential) to a more electronegative (lower redox potential) state. This movement is energetically favorable and is considered a downhill journey.

4. **Conclusion:**
- Both the assertion and the reason are true. The assertion correctly describes the nature of electron movement in the ETS as a downhill journey, and the reason accurately explains this by stating that electrons move from high redox potential to low redox potential. Therefore, the reason is indeed the correct explanation for the assertion.

5. **Final Answer:**
- Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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