During heat shock, the temperature used for giving thermal shock to the bacterium is

Options

A. `82^(@)C`
B. `100^(@)C`
C. Liquid nitrogen
D. `42^(@)C`

Answer

**Step-by-Step Solution:**

1. **Understanding Heat Shock Method**: The heat shock method is a technique used in molecular biology, particularly for the transformation of bacteria. It involves exposing bacteria to a sudden increase in temperature to facilitate the uptake of plasmid DNA.

2. **Purpose of Heat Shock**: The primary goal of the heat shock is to increase the fluidity of the bacterial cell membrane. This alteration in membrane fluidity allows the formation of pores in the membrane.

3. **Temperature Range for Heat Shock**: The typical temperature used for heat shock in bacteria is around 42 degrees Celsius. This temperature is optimal for creating the necessary conditions for transformation.

4. **Process of Transformation**: When the bacteria are subjected to the heat shock at 42 degrees Celsius, the increased temperature creates pores in the bacterial membrane. This allows plasmid DNA to enter the bacterial cells.

5. **Conclusion**: Therefore, the correct temperature used for giving thermal shock to the bacterium during the heat shock method is **42 degrees Celsius**.

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