Respiratory rate increases twice/thrice with every `10^(@)C` rise in temperature. This is called

Options

A. Haldane effect
B. Hamburger phenomenon
C. Chloride shift
D. Vant Hoffs law

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that the respiratory rate increases two to three times with every 10°C rise in temperature. We need to identify what this phenomenon is called.

2. **Identifying the Concept**: The relationship between temperature and respiratory rate is a physiological response observed in many organisms. This response can be explained by Van't Hoff's law, which states that for every 10°C increase in temperature, the rate of a biochemical reaction (including respiration) can double or triple.

3. **Applying Van't Hoff's Law**: According to Van't Hoff's law, if the temperature of a system increases, the equilibrium shifts, and the rate of metabolic processes, including respiration, increases. This is particularly relevant for organisms that do not maintain homeostasis.

4. **Considering Homeothermic Organisms**: In mammals (including humans), the body temperature is regulated and remains relatively constant (around 37°C). Therefore, while Van't Hoff's law applies to many organisms, its effects are not typically observed in homeothermic organisms under normal conditions.

5. **Conclusion**: The phenomenon where the respiratory rate increases two to three times with every 10°C rise in temperature is referred to as **Van't Hoff's law**.

**Final Answer**: This phenomenon is called **Van't Hoff's law**.

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