Hammerling experimented on:-

Options

A. Chlorella
B. Acetabularia
C. Chara
D. Ulva

Answer

**Step-by-Step Solution:**

1. **Identify the Experimenter**: The question asks about the experiments conducted by Hammerling. It is important to recognize that Hammerling is known for his work on the role of the nucleus in cells.

2. **Year of Experiment**: Hammerling conducted his significant experiment in the year 1943. This detail is crucial as it places the experiment in a historical context.

3. **Species Used**: Hammerling specifically experimented on a species known as Acetabularia, which is a type of green algae. This is the key organism he used in his experiments.

4. **Nature of the Experiment**: In his experiment, Hammerling removed the nucleus from Acetabularia and then performed grafting with another Acetabularia species. This was done to observe the effects of the nucleus on the characteristics of the organism.

5. **Conclusion**: Based on the information gathered, it is clear that Hammerling experimented on Acetabularia, which is the correct answer to the question.

**Final Answer**: Hammerling experimented on Acetabularia.

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