Hammerling experimented on:-

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Subject of the Experiment**: The question asks about the organism that Hammerling experimented on. The options provided are Cholera, Acetobularia, Chiara, and Ulva.

2. **Recall Hammerling's Experiment**: It is important to remember that Hammerling is known for his work with a specific type of green algae, which is Acetobularia.

3. **Understand the Structure of Acetobularia**: Acetobularia is a unicellular green alga that has three main parts:
- The rhizoid (base) which contains the nucleus,
- The stalk,
- The cap.

4. **Describe the Experiment**: Hammerling performed grafting experiments where he grafted the stalk of one species of Acetobularia onto the rhizoid of another species.

5. **Analyze the Results**: After the grafting, the cap that developed on the grafted cell matched the species of the rhizoid (the base) rather than the stalk. This indicated that the genetic information responsible for the type of cap is located in the nucleus of the rhizoid.

6. **Conclude the Findings**: The experiment demonstrated that the nucleus (located in the rhizoid) directs cellular development and controls heredity. Therefore, the correct answer to the question is that Hammerling experimented on Acetobularia.

7. **Final Answer**: The correct option is **Acetobularia**.

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