Which of the following is not correctly correlate with neural system?
i. The neural system of all animals is composed of highly specialised cells called neurous which can detect receive and transmit different kinds of stimuli
ii. The neural organisation is very simple is lower invertebrates
iii. Neural system of Hydra is composed of a network of neurons.
iv. The neural system is better organised in insects, where a brain is present along with a number of ganglia and neural tissues
V. The vertebrates have a more developed neural system .
vi. Neural system of earthworm is composed of a network of neurons

Options

A. ii,iii and v
B. iii and iv
C. iii and vi
D. Only vi

Answer

To determine which statement is not correctly correlated with the neural system, we will analyze each option step by step:

### Step-by-Step Solution:

1. **Statement i**: "The neural system of all animals is composed of highly specialised cells called neurons which can detect, receive, and transmit different kinds of stimuli."
- **Analysis**: This statement is correct. Neurons are indeed the specialized cells responsible for the transmission of signals in the nervous system.

2. **Statement ii**: "The neural organisation is very simple in lower invertebrates."
- **Analysis**: This statement is also correct. Lower invertebrates, such as jellyfish, have a simple nerve net structure rather than a centralized nervous system.

3. **Statement iii**: "Neural system of Hydra is composed of a network of neurons."
- **Analysis**: This statement is correct. Hydra has a decentralized nerve net, which is a characteristic of cnidarians.

4. **Statement iv**: "The neural system is better organised in insects, where a brain is present along with a number of ganglia and neural tissues."
- **Analysis**: This statement is correct. Insects have a well-organized nervous system that includes a brain and ganglia.

5. **Statement v**: "The vertebrates have a more developed neural system."
- **Analysis**: This statement is correct. Vertebrates possess a complex nervous system with a defined brain and spinal cord.

6. **Statement vi**: "Neural system of earthworm is composed of a network of neurons."
- **Analysis**: This statement is incorrect. The neural system of earthworms is organized into a ventral nerve cord with segmental ganglia, not just a network of neurons.

### Conclusion:
The statement that is not correctly correlated with the neural system is **Statement vi**: "Neural system of earthworm is composed of a network of neurons."

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