Chordates differ from other animals in having

Options

A. Notochord
B. Ventral nerve cord
C. Dorsal heart
D. Schizocoel

Answer

### Step-by-Step Solution:

1. **Understanding Chordates**: Chordates are a diverse group of animals that share specific characteristics during some stage of their development. The defining feature of chordates is the presence of a notochord.

2. **Identifying Key Features**: The key features that distinguish chordates from other animals (non-chordates) include:
- **Notochord**: A flexible rod-like structure that provides support.
- **Dorsal Hollow Nerve Cord**: Unlike other animals that may have a solid nerve cord, chordates possess a hollow nerve cord located along the back.
- **Pharyngeal Slits**: These are openings in the throat region that may develop into gills in aquatic species.
- **Ventral Heart**: The heart is located on the ventral side (belly side) of the body.
- **Postanal Tail**: A tail that extends beyond the anus, present in many chordates.

3. **Comparing with Non-Chordates**: In contrast to chordates, non-chordates lack these features. For instance:
- Non-chordates do not have a notochord.
- Their central nervous system is typically solid and located ventrally.
- They do not possess pharyngeal slits or a postanal tail.

4. **Conclusion**: The presence of a notochord is the primary characteristic that differentiates chordates from other animals. Thus, the correct answer to the question is that chordates differ from other animals in having a notochord.

### Final Answer:
Chordates differ from other animals in having a **notochord**.

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