Nerve cord of chordates is

Options

A. Dorsal
B. Hollow
C. Ventral
D. Both A and B

Answer

To answer the question regarding the nerve cord of chordates, we can break down the information step by step.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A) Dorsal
- B) Holo
- C) Ventral
- D) Both A and B

2. **Understanding the Nerve Cord**: The nerve cord in chordates is a significant feature. It is located in a specific position relative to other structures in the body.

3. **Dorsal Position**: The nerve cord of chordates is **dorsal** to the notochord. This means it is situated on the back side of the organism, which is a characteristic feature of chordates.

4. **Hollow Structure**: The nerve cord is also described as **hollow**. This means it is not solid but rather forms a tube-like structure. The term "holo" refers to this hollow characteristic.

5. **Formation from Ectoderm**: The dorsal hollow nerve cord develops from the ectoderm during embryonic development, forming a structure that will eventually become part of the central nervous system, which includes the brain and spinal cord.

6. **Comparison with Other Groups**: In contrast, invertebrates typically have a **ventral** nerve cord, meaning it is located on the belly side of the organism. This distinction helps to differentiate chordates from other animal groups.

7. **Conclusion**: Since the nerve cord of chordates is both dorsal and hollow, the correct answer to the question is **option D) Both A and B**.

### Final Answer:
The nerve cord of chordates is **dorsal and hollow**. Therefore, the correct answer is **option D) Both A and B**.

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