The feature that is not a characteristic of protochordata?

Options

A. Presence of notochord
B. Bilateral symmetry and coelom
C. Jointed legs
D. Presence of circulatory system

Explanation

To determine the feature that is not a characteristic of protochordata, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Protochordata**: Protochordata refers to primitive chordates. The prefix "proto" means primitive, indicating that these organisms have some features of chordates but are not fully developed.

2. **Identify Key Characteristics of Protochordata**:
- **Presence of Notochord**: All protochordates possess a notochord, which is a flexible rod-like structure that provides support.
- **Bilateral Symmetry**: Protochordates exhibit bilateral symmetry, meaning their body can be divided into two equal halves.
- **Coelom**: They have a coelom, which is a fluid-filled body cavity.
- **Circulatory System**: Protochordates possess a circulatory system.

3. **Examine the Options**: The question typically provides several options. In this case, we need to identify which one does not belong to the characteristics of protochordata.
- **Option 1**: Presence of notochord - This is a characteristic of protochordata.
- **Option 2**: Bilateral symmetry - This is also a characteristic of protochordata.
- **Option 3**: Coelom - This is a characteristic of protochordata.
- **Option 4**: Jointed legs - This is NOT a characteristic of protochordata, as jointed legs are features of arthropods, not protochordates.

4. **Conclusion**: The feature that is not a characteristic of protochordata is the presence of jointed legs.

### Final Answer:
The feature that is not a characteristic of protochordata is **jointed legs**.

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