Significance of 'heat shock' method in bacterial transformation is to facilitate

Options

A. binding of DNA to the cell wall
B. uptake of DNA through membrane transport proteins
C. uptake of DNA through transient pores in the bacterial cell wall
D. expression of antibiotic resistance gene

Answer

**Step-by-Step Solution:**

1. **Understanding the Heat Shock Method**: The heat shock method is a technique used in molecular biology to facilitate the uptake of foreign DNA by bacterial cells. It involves subjecting competent bacterial cells to a sudden increase in temperature.

2. **Making Bacterial Cells Competent**: Before the heat shock, bacterial cells are treated to make them competent, meaning they are capable of taking up DNA. This is typically done by incubating the cells on ice, which prepares them for the heat shock.

3. **Applying Heat Shock**: The competent bacterial cells are then subjected to a brief heat shock at 42 degrees Celsius. This sudden increase in temperature causes the bacterial cell membranes to become more permeable.

4. **Formation of Temporary Pores**: The heat shock creates transient pores in the bacterial cell wall. These pores allow the foreign DNA to enter the bacterial cells.

5. **Returning to Ice**: After the heat shock, the cells are placed back on ice. This helps to stabilize the cell membranes and allows the DNA to be retained inside the cells.

6. **Conclusion**: The significance of the heat shock method in bacterial transformation is primarily to facilitate the uptake of DNA through the creation of temporary or transient pores in the bacterial cell wall.

**Final Answer**: The significance of the 'heat shock' method in bacterial transformation is to facilitate the uptake of DNA through the creation of temporary or transient pores in the bacterial cell wall.

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