Griffith conducted his transformation experiments on

Options

A. Escherichia coli
B. Streptococcus pyogenes
C. Diplococcus pneumoniae
D. Streptomyces griseus

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the organism on which Griffith conducted his transformation experiments.

2. **Historical Context**: Frederick Griffith conducted his transformation experiments in 1928. His work was pivotal in understanding genetic material and the process of transformation in bacteria.

3. **Identifying the Organism**: In his experiments, Griffith used the bacterium *Diplococcus pneumoniae*, which is also known as *Streptococcus pneumoniae*.

4. **Experimental Design**: Griffith used two different strains of *Diplococcus pneumoniae*:
- **Smooth strain (S strain)**: This strain was virulent and capable of causing disease.
- **Rough strain (R strain)**: This strain was non-virulent and did not cause disease.

5. **Conclusion of the Experiment**: Through his experiments, Griffith demonstrated that the genetic material could be transferred from the smooth strain to the rough strain, transforming the rough strain into a virulent form. This process was termed "transformation."

6. **Evaluating the Options**:
- *Escherichia coli* (E. coli) was not used in Griffith's experiments.
- *Streptococcus pyogenes* is a different bacterium and was not involved in his work.
- *Diplococcus pneumoniae* is the correct organism used in the transformation experiments.
- *Streptomyces griseus* is also not related to Griffith's experiments.

7. **Final Answer**: The correct answer is *Diplococcus pneumoniae*.

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