Transformation in Diplococcus by heat- killed extract was discovered by

Options

A. Brown
B. Griffith
C. Fleming
D. McLeod.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who discovered the transformation in Diplococcus (specifically referring to the bacterium Streptococcus pneumoniae) by heat-killed extract.

2. **Review the Options**: The options provided are:
- A) Brown
- B) Griffith
- C) Fleming
- D) McLeod

3. **Recall Historical Context**: The transformation process in bacteria was notably studied in the 1920s. Frederick Griffith conducted pivotal experiments during this time.

4. **Understand Griffith's Experiment**: In 1928, Frederick Griffith performed experiments using two strains of Streptococcus pneumoniae:
- Type 3S (smooth and virulent)
- Type 2R (rough and non-virulent)

5. **Describe the Experiment**: Griffith discovered that when he mixed heat-killed Type 3S bacteria with live Type 2R bacteria, the Type 2R bacteria transformed into Type 3S, acquiring virulence. This indicated that genetic information could be transferred between bacteria, a process now known as transformation.

6. **Select the Correct Answer**: Given the information, the scientist who discovered transformation in Diplococcus by heat-killed extract is Frederick Griffith. Therefore, the correct answer is option B) Griffith.

7. **Conclusion**: The final answer to the question is Frederick Griffith.

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