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

Options

A. a) binding of DNA to the cell wall
B. b) uptake of DNA through membrane transport proteins
C. c) uptake of DNA through transient pores in the bacterial cell wall
D. 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 make bacterial cells competent, meaning they can take up foreign DNA, such as recombinant DNA.

2. **Incubation on Ice**: Initially, the bacterial cells are incubated with the recombinant DNA on ice. This step helps to stabilize the DNA and the cells, preparing them for the subsequent heat shock.

3. **Heat Shock Application**: After the ice incubation, the cells are subjected to a sudden increase in temperature (approximately 42 degrees Celsius). This rapid temperature change is critical as it creates a thermal imbalance.

4. **Formation of Transient Pores**: The heat shock causes the bacterial cell membrane to become more permeable, leading to the formation of transient pores in the cell wall. These pores allow the recombinant DNA to enter the bacterial cells.

5. **Cooling Down Again**: Following the heat shock, the cells are placed back on ice. This cooling step helps to stabilize the cells and the DNA inside them, allowing for successful uptake.

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

**Final Answer**: The correct significance of the heat shock method in bacterial transformation is the uptake of DNA through transient pores in the bacterial cell wall.

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