According to folded fibre model, the diameter of chromatin fiber is

Options

A. `30A^@`
B. 230 nm
C. `230A^@`
D. `23A^@`

Answer

To solve the question regarding the diameter of chromatin fiber according to the folded fiber model, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromatin Structure**:
- Chromatin is a complex of DNA and proteins found in the nucleus of eukaryotic cells. It is organized into structures called chromosomes during cell division.

2. **Identifying the Models of Chromatin Organization**:
- There are several models that explain the structure of chromatin, with the two most accepted being the nucleosome model and the folded fiber model.

3. **Focusing on the Folded Fiber Model**:
- The folded fiber model was proposed by scientist Dupra. This model describes chromosomes as long, coiled chromatin fibers.

4. **Determining the Diameter of Chromatin Fiber**:
- According to the folded fiber model, the diameter of the chromatin fiber is stated to range from 200 to 250 angstroms (Å).

5. **Finding the Approximate Value**:
- The approximate value for the diameter of chromatin fiber, as per the folded fiber model, is 230 angstroms (Å).

6. **Selecting the Correct Option**:
- Given the options provided in the question, the correct answer is 230 angstroms (Å), which corresponds to option 3.

### Final Answer:
The diameter of chromatin fiber according to the folded fiber model is approximately **230 angstroms (Å)**.

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