Ladder like nervous system with ventral nerve chord is present in

Options

A. Cnidaria
B. Plathyhelminthes
C. Annelida
D. Arthropoda

Answer

To determine which group of animals possesses a ladder-like nervous system with a ventral nerve cord, we can analyze the options provided:

1. **Understanding the Nervous System**: The term "ladder-like nervous system" refers to a specific arrangement of nerve cords and connections that resemble a ladder. This type of nervous system is typically found in certain invertebrates.

2. **Identifying the Options**:
- **Nadiria**: This phylum includes organisms like jellyfish and corals, which have a nerve net rather than a ladder-like structure. Therefore, this option is incorrect.
- **Platyhelminthes**: This phylum includes flatworms, which are known for having a ladder-like nervous system and a ventral nerve cord. This option is likely correct.
- **Annelida**: Annelids, such as earthworms, have a more complex nervous system with a ventral nerve cord but do not exhibit a ladder-like arrangement. Thus, this option is incorrect.
- **Arthropoda**: Arthropods, including insects and crustaceans, have a segmented nervous system but do not have a ladder-like structure. This option is also incorrect.

3. **Conclusion**: Based on the analysis, the only group that fits the description of having a ladder-like nervous system with a ventral nerve cord is **Platyhelminthes**.

**Final Answer**: The ladder-like nervous system with a ventral nerve cord is present in **Platyhelminthes**.

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