Absence of oxygen will arrest which of the following
i. EMP Pathway
ii. TCA cycle
iii. Chemiosmosis coupling
iv. Lactate fermentation

Options

A. i, ii & iii
B. ii, iii & iv
C. Only i & ii
D. only ii & iii

Answer

To determine which processes will be arrested in the absence of oxygen, we need to analyze each option provided in the question:

### Step-by-Step Solution:

1. **Understanding the EMP Pathway**:
- The EMP (Embden-Meyerhof-Parnas) pathway is the glycolytic pathway that breaks down glucose into pyruvate.
- This process does not require oxygen and can occur under anaerobic conditions.
- **Conclusion**: The EMP pathway will **not** be arrested in the absence of oxygen.

2. **Understanding the TCA Cycle**:
- The TCA (Tricarboxylic Acid) cycle, also known as the Krebs cycle, requires oxygen indirectly because it relies on the electron transport chain (ETC) for the regeneration of NAD+.
- The ETC requires oxygen as the final electron acceptor. Without oxygen, the ETC cannot function, leading to a halt in the TCA cycle.
- **Conclusion**: The TCA cycle **will** be arrested in the absence of oxygen.

3. **Understanding Chemiosmosis Coupling**:
- Chemiosmosis coupling is involved in ATP production through oxidative phosphorylation, which also requires oxygen.
- Oxygen is essential for the ETC, and without it, ATP production through chemiosmosis cannot occur.
- **Conclusion**: Chemiosmosis coupling **will** be arrested in the absence of oxygen.

4. **Understanding Lactate Fermentation**:
- Lactate fermentation is an anaerobic process that occurs in the absence of oxygen, allowing organisms to generate energy by converting pyruvate into lactate.
- **Conclusion**: Lactate fermentation will **not** be arrested in the absence of oxygen.

### Final Answer:
In summary, the processes that will be arrested in the absence of oxygen are:
- ii. TCA cycle
- iii. Chemiosmosis coupling

Thus, the correct answer is: **ii and iii**.