A sudden change from anaerobic to aerobic process produces

Options

A. Pasteur effect
B. Emerson effect
C. Blackman's law
D. Charagaffs rule.

Answer

**Step-by-Step Solution:**

1. **Understanding the Processes**:
- Anaerobic respiration occurs in the absence of oxygen, while aerobic respiration requires oxygen.
- Organisms can switch from anaerobic to aerobic respiration depending on the availability of oxygen.

2. **Identifying the Effects of Switching**:
- When an organism that has been undergoing anaerobic respiration suddenly has access to oxygen, it experiences changes in metabolic processes.

3. **Recognizing the Pasteur Effect**:
- The phenomenon where the presence of oxygen leads to a decrease in the rate of fermentation (sugar breakdown) and an increase in the rate of glycolysis is known as the Pasteur effect.
- This effect was named after Louis Pasteur, who studied fermentation processes.

4. **Eliminating Other Options**:
- The Emerson effect and Blackman’s effect are related to photosynthesis, while Chargaff's rule pertains to the base pairing in DNA. Thus, they are not relevant to the question.

5. **Conclusion**:
- Therefore, the correct answer to the question is the Pasteur effect, which describes the changes that occur when an organism switches from anaerobic to aerobic respiration.

**Final Answer**: A) Pasteur effect

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