Read the following statements regarding agarose gel electrophoresis and select the CORRECT ones.
I. The longest DNA fragments are nearest to the anode.
II. The matrix of the gel is a natural polymer obtained from seaweeds.
III The process is used to check the progression of restriction enzyme digestion.
IV. The fragments of DNA separated due to the sieving effect provided by agarose gel.

Options

A. I, II III and IV
B. III and IV only
C. II, III and IV only
D. I, II and III only

Answer

To solve the question regarding agarose gel electrophoresis, we will analyze each statement one by one to determine which ones are correct.

### Step-by-Step Solution:

1. **Statement I: The longest DNA fragments are nearest to the anode.**
- This statement is **incorrect**. In agarose gel electrophoresis, DNA fragments are negatively charged and move towards the anode (positive electrode). The longest DNA fragments move the slowest because they get entangled in the gel matrix, while the shortest fragments move the fastest and are nearest to the anode.

2. **Statement II: The matrix of the gel is a natural polymer obtained from seaweeds.**
- This statement is **correct**. Agarose, the gel used in electrophoresis, is a natural polymer derived from seaweed. It is a polysaccharide that forms a gel-like matrix when dissolved in buffer and cooled.

3. **Statement III: The process is used to check the progression of restriction enzyme digestion.**
- This statement is **correct**. Agarose gel electrophoresis is commonly used to analyze DNA fragments after they have been cut by restriction enzymes. By running the digested DNA on a gel, one can visualize the sizes of the resulting fragments and confirm whether the digestion has occurred.

4. **Statement IV: The fragments of DNA separated due to the sieving effect provided by agarose gel.**
- This statement is **correct**. The agarose gel acts as a sieve, allowing smaller DNA fragments to move through the gel more easily than larger fragments. This sieving effect is what enables the separation of DNA fragments based on size.

### Conclusion:
The correct statements are:
- Statement II: Correct
- Statement III: Correct
- Statement IV: Correct

Thus, the correct option includes statements II, III, and IV.

### Final Answer:
The correct statements are II, III, and IV.

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