Which one has a tree-like branched from?

Options

A. Pennatula
B. Gorgonia
C. Physalia
D. Porpita.

Answer

To answer the question "Which one has a tree-like branched form?", we can analyze the options provided:

1. **Panatula**: This organism is commonly known as a sea pen. Sea pens have a feather-like structure resembling quill pens, but they do not exhibit a tree-like branched form. Therefore, this option is incorrect.

2. **Gorgonia**: Gorgonia is a type of soft coral, often referred to as sea fan. It has a distinct tree-like branched appearance due to the arrangement of its polyps, which are structured in rows and made of calcite. This characteristic makes Gorgonia the correct answer to the question.

3. **Physalia**: Known as blue bottles or man-of-war, Physalia resembles a sail ship and does not have a tree-like branched form. Thus, this option is also incorrect.

4. **Porpita**: This organism is referred to as blue button jelly. It is known for causing irritation upon contact but does not possess a tree-like branched form. Therefore, this option is incorrect as well.

In conclusion, the organism that has a tree-like branched form is **Gorgonia**.

### Step-by-Step Solution:
1. **Identify the options**: Panatula, Gorgonia, Physalia, Porpita.
2. **Analyze Panatula**: Recognized as sea pen, does not have a tree-like structure.
3. **Analyze Gorgonia**: Known as sea fan, has a tree-like branched form, making it the correct answer.
4. **Analyze Physalia**: Known as blue bottles or man-of-war, does not exhibit a tree-like structure.
5. **Analyze Porpita**: Known as blue button jelly, does not have a tree-like branched form.
6. **Conclusion**: The correct answer is Gorgonia.