Chordates differ from non-chordates in having
(a) Bilateral symmetry
(b) Heart
(c) Notochord
(d) Nerve cord

Options

A. Bilateral symmetry
B. Heart
C. Notochord
D. Nerve cord

Answer

To solve the question regarding the differences between chordates and non-chordates, we will analyze each option provided:

1. **Understanding the options**:
- (a) Bilateral symmetry
- (b) Heart
- (c) Notochord
- (d) Nerve cord

2. **Analyzing the options**:
- **Option (a): Bilateral symmetry**: Both chordates and many non-chordates exhibit bilateral symmetry. Therefore, this feature does not differentiate chordates from non-chordates.

- **Option (b): Heart**: While many chordates have a heart, some non-chordates also possess a circulatory system with a heart-like structure. Thus, this is not a definitive differentiating feature.

- **Option (c): Notochord**: This is a defining characteristic of chordates. Chordates possess a notochord at some stage of their development, which is absent in non-chordates. This is the primary feature that distinguishes chordates from non-chordates.

- **Option (d): Nerve cord**: Chordates have a dorsal hollow nerve cord, while some non-chordates have different types of nerve cords. However, this feature is not as definitive as the presence of a notochord.

3. **Conclusion**: Based on the analysis, the presence of a notochord is the key feature that differentiates chordates from non-chordates. Therefore, the correct answer is **(c) Notochord**.