Protein is mostly the respiratory substrate in

Options

A. protoplasmic respiration
B. floating respiration
C. anaerobic respiration
D. respiration of oily seeds

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the condition in which protein serves as the primary respiratory substrate. This means we need to identify a specific type of respiration where proteins are predominantly used for energy production.

2. **Analyzing the Options**: We have four options to consider:
- Option 1: Protoplasmic respiration
- Option 2: Floating respiration
- Option 3: Anaerobic respiration
- Option 4: Respiration of oily seeds

3. **Evaluating Each Option**:
- **Protoplasmic Respiration**: This type of respiration occurs when carbohydrates and fats are not available. In such cases, cells utilize proteins as a substrate. This process is less efficient and produces ammonia as a by-product, which is toxic to cells.
- **Floating Respiration**: This term does not refer to a recognized type of respiration involving proteins.
- **Anaerobic Respiration**: This type of respiration typically involves glucose or other carbohydrates, not proteins.
- **Respiration of Oily Seeds**: While oily seeds may utilize fats as a substrate, this does not specifically indicate that proteins are the primary substrate.

4. **Conclusion**: Based on the analysis, the correct answer is **Option 1: Protoplasmic respiration**, as it is the condition where proteins are primarily used as the respiratory substrate when other substrates are not available.

**Final Answer**: Protein is mostly the respiratory substrate in **Protoplasmic respiration**.

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