Switch over from anaerobic to aerobic mode of respiration is accompanied by reduction in consumption of respiratory substrate. The phenomenon is called

Options

A. Warburg effect
B. Pasteur effect
C. Oxygen coefficient
D. Liebig's law.

Answer

To answer the question regarding the phenomenon that describes the switch from anaerobic to aerobic respiration accompanied by a reduction in the consumption of respiratory substrates, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding Respiration Types**:
- Respiration can be classified into two main types: aerobic and anaerobic.
- Aerobic respiration requires oxygen and involves multiple steps (glycolysis, oxidative decarboxylation, Krebs cycle, and electron transport chain) to produce ATP.
- Anaerobic respiration does not require oxygen and involves fewer steps, resulting in a quicker, but less efficient, ATP production.

**Hint**: Remember the key differences between aerobic and anaerobic respiration, especially regarding oxygen usage and ATP yield.

2. **Switching Modes of Respiration**:
- Cells typically prefer aerobic respiration for efficient ATP production. However, in conditions where oxygen is scarce, cells switch to anaerobic respiration to quickly generate ATP.
- This switch is particularly evident in rapidly dividing cells, such as cancer cells, which require energy quickly.

**Hint**: Consider why cells might switch to anaerobic respiration and the implications of rapid energy needs.

3. **The Role of Tumor Cells**:
- Tumor cells often rely on anaerobic respiration due to their rapid division and high energy demands. This leads to a decrease in the consumption of aerobic substrates (like glucose) when they switch back to aerobic respiration.

**Hint**: Think about the relationship between energy demands of cells and their metabolic processes.

4. **Identifying the Phenomenon**:
- The phenomenon where there is a reduction in the consumption of respiratory substrates when switching from anaerobic to aerobic respiration is known as the **Warburg Effect**.
- This effect was named after Otto Warburg, who studied the metabolism of cancer cells and noted their preference for anaerobic respiration even in the presence of oxygen.

**Hint**: Focus on the historical context and the significance of the Warburg Effect in cancer research.

### Final Answer:
The phenomenon is called the **Warburg Effect**.