The term 'Nuclein' for the genetic material was used by:

Options

A. Franklin
B. Meischer
C. Chargaff
D. Mendel

Answer

To solve the question regarding who first used the term 'Nuclein' for genetic material, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question provides multiple choices, including Franklin, Mischer, Chargaff, and Mendel.

2. **Understanding the Contributions**:
- **Franklin**: Rosalind Franklin is known for her work in X-ray crystallography, which helped in understanding the structure of DNA, but she did not coin the term 'nuclein'.
- **Mischer**: Frederick Mischer is known for his discovery of the substance in the nucleus, which he named 'nuclein' in 1869. This was a significant step in identifying genetic material.
- **Chargaff**: Erwin Chargaff is famous for his rules regarding the ratios of nucleotides in DNA, but he did not use the term 'nuclein'.
- **Mendel**: Gregor Mendel is known as the father of genetics for his work on inheritance patterns, but he did not use the term 'nuclein'.

3. **Conclusion**: Based on the contributions of each scientist, the correct answer is **Mischer**, as he was the first to discover and name the genetic material as 'nuclein'.

### Final Answer:
The term 'Nuclein' for the genetic material was used by **Frederick Mischer**.

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