Which of the following are not required while performing a transformation experiment ?

Options

A. Insert DNA
B. Ice cold calcium chloride
C. `90^(@)`
D. Bacterial cells

Answer

To determine which of the following are not required while performing a transformation experiment, we need to understand the components and conditions necessary for the process of transformation. Here’s a step-by-step breakdown:

### Step 1: Understand the Transformation Experiment
A transformation experiment involves introducing foreign DNA into a bacterial cell. This is a crucial process in biotechnology for genetic engineering.

### Step 2: Identify Required Components
1. **Foreign DNA**: This is the DNA that we want to introduce into the bacterial cell.
2. **Competent Bacterial Cells**: These are bacterial cells that have been treated to allow them to take up foreign DNA.
3. **Divalent Cations (e.g., Calcium Chloride)**: These ions help to increase the permeability of the bacterial cell membrane, facilitating the uptake of DNA.
4. **Heat Shock**: A brief exposure to a higher temperature (around 42°C) is used to encourage the uptake of DNA by the cells.
5. **Ice Cold Treatment**: This is used before and after the heat shock to stabilize the cells.

### Step 3: Identify the Irrelevant Component
From the components mentioned, we can see that:
- **90 degrees Celsius** is not required. The heat shock step specifically requires a temperature of 42 degrees Celsius, not 90 degrees.

### Conclusion
Thus, the component that is not required while performing a transformation experiment is **90 degrees Celsius**.

### Final Answer
The correct answer is **90 degrees Celsius**.

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