Chorda dorsalis is

Options

A. Dorsal solid nerve cord
B. Dorsal hollow nerve cord
C. Notochord
D. Stomochord

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Chorda Dorsalis":**
- The term "chorda dorsalis" refers to a specific anatomical structure found in chordates. It is essential to identify what this structure represents in biological terms.

2. **Analyzing the Options Provided:**
- The options given are:
1. Dorsal solid nerve cord
2. Dorsal hollow nerve cord
3. Notochord
4. Stomochord

3. **Eliminating Incorrect Options:**
- The first option, "dorsal solid nerve cord," is incorrect because chorda dorsalis is not a nerve cord.
- The second option, "dorsal hollow nerve cord," is also incorrect for the same reason; chorda dorsalis is not a type of nerve cord.

4. **Identifying the Correct Option:**
- The third option, "notochord," is indeed the correct answer. The notochord is a rod-like structure that provides support and is present in the embryonic stages of all chordates.
- The fourth option, "stomochord," is not a recognized structure in chordates. It refers to a term that combines "stoma" (meaning mouth) and "chord," but it is not applicable here.

5. **Conclusion:**
- Based on the analysis, the correct answer to the question "Chorda dorsalis is" is the third option: **notochord**.

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