Archaebacteria that flourish in temperature above `100^(@)C` have special_________molecules that do not coagulate at high temperature and remain functional.

Options

A. carbohydrate
B. ester
C. protein
D. fat

Answer

**Step-by-Step Solution:**

1. **Understanding the Environment**: The question mentions archaebacteria that thrive in temperatures above 100°C. These organisms are known to inhabit extreme environments, such as geothermal vents and hot springs.

2. **Role of Temperature**: Temperature is a critical abiotic factor that influences the metabolic activities of living organisms. High temperatures can affect the kinetics of enzymes, which are crucial for biochemical reactions.

3. **Enzyme Stability**: Enzymes require specific conditions, including optimal temperature and pH, to function effectively. At high temperatures, many enzymes can denature, losing their functional shape and activity.

4. **Thermostable Enzymes**: To survive in extreme heat, archaebacteria must possess enzymes that remain functional at high temperatures. These enzymes are referred to as thermostable enzymes.

5. **Chemical Nature of Enzymes**: Most enzymes are proteins. Therefore, the special molecules that allow archaebacteria to function at high temperatures are likely to be proteinaceous in nature.

6. **Conclusion**: Since the question asks for the type of molecules that do not coagulate at high temperatures and remain functional, the correct answer is "proteins."

**Final Answer**: Archaebacteria that flourish in temperatures above 100°C have special **proteins** that do not coagulate at high temperature and remain functional.

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