In electrophoresis , the DNA sample is loaded in the gel

Options

A. away from the wells.
B. towards the positive electrode .
C. towards the negative electrode.
D. Both (A) and (C)

Answer

To solve the question regarding the loading of DNA samples in electrophoresis, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding Electrophoresis**:
- Electrophoresis is a technique used to separate molecules, such as DNA, based on their size and charge when an electric field is applied.

**Hint**: Remember that electrophoresis separates molecules by their size and charge.

2. **Agarose Gel**:
- In DNA electrophoresis, agarose gel is commonly used. The gel acts as a medium through which the DNA fragments can migrate.

**Hint**: Agarose gel is specifically designed for separating DNA fragments.

3. **Charge of DNA**:
- DNA molecules are negatively charged due to their phosphate backbone. This means that when an electric field is applied, the DNA will move towards the positive electrode.

**Hint**: Recall that DNA is negatively charged, which influences its movement in an electric field.

4. **Loading the Sample**:
- The DNA samples are loaded into wells that are positioned near the negative electrode. This is because they need to migrate towards the positive electrode during electrophoresis.

**Hint**: Think about where the DNA needs to go (towards the positive electrode) and where it must be loaded (near the negative electrode).

5. **Analyzing the Options**:
- The question provides several options regarding where the DNA sample is loaded:
- A) Away from the wells
- B) Towards the positive electrode
- C) Towards the negative electrode
- D) Both A and C

- Based on our understanding, the correct answer is that the DNA sample is loaded towards the negative electrode (option C).

**Hint**: Eliminate options that contradict the movement of negatively charged DNA.

### Final Answer:
The DNA sample in electrophoresis is loaded in the gel towards the negative electrode.