Bacterical endospores are perennating structures which can tolerate extremes of high temperature due to the presence of :

Options

A. cellulosic thick cell wall
B. tight cross-linking of amino sugars
C. `Ca^(+2)` and dipicolinic acid
D. teichoic acid

Answer

To answer the question regarding why bacterial endospores can tolerate extremes of high temperature, we will break down the information step by step.

### Step-by-Step Solution:

1. **Understanding Bacterial Endospores**:
- Bacterial endospores are specialized structures formed by certain bacteria to survive unfavorable conditions. They are highly resistant to extreme environmental factors, including high temperatures.

2. **Structure of Endospores**:
- The endospore consists of several layers:
- The core, which contains the bacterial DNA and essential cellular components.
- The germ cell wall, which is surrounded by a protective coat.
- The cortex, made of peptidoglycan, which provides additional protection.
- An inner membrane that acts as a barrier against harmful substances.

3. **Key Components for Heat Resistance**:
- The core of the endospore contains a significant amount of **Dipicolinic acid**. This compound plays a crucial role in stabilizing the DNA and proteins within the endospore.
- Additionally, the presence of **calcium ions** (specifically in the form of calcium dipicolinate) contributes to the structural integrity and heat resistance of the endospore.

4. **Mechanism of Tolerance**:
- The combination of Dipicolinic acid and calcium ions helps to maintain the dormancy of the endospore and protects it from damage caused by high temperatures, radiation, and enzymatic actions.

5. **Conclusion**:
- Therefore, the ability of bacterial endospores to tolerate extreme high temperatures is primarily due to the presence of **calcium and Dipicolonic acid**.

### Final Answer:
The correct answer is that bacterial endospores can tolerate extremes of high temperature due to the presence of **calcium and Dipicolonic acid**.

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