In Hydra , the neural organisation is comprised of

Options

A. a network of neurons
B. CNS and PNS
C. only CNS
D. only PNS

Answer

To solve the question regarding the neural organization in Hydra, we can follow these steps:

### Step-by-Step Solution

1. **Understanding Hydra's Nervous System**:
- Hydra is a simple organism that belongs to the phylum Cnidaria. It has a relatively simple nervous system compared to more complex organisms.

2. **Identifying the Components of Hydra's Nervous System**:
- In Hydra, the nervous system is made up of nerve cells (neurons). These neurons are not organized into a central nervous system (CNS) or a peripheral nervous system (PNS) as seen in higher organisms.

3. **Nature of Neurons in Hydra**:
- The neurons in Hydra are described as apolar, meaning they do not have distinct axons and dendrites like those found in more complex animals. Instead, they are interconnected and form a diffuse nerve net.

4. **Function of the Nervous System**:
- This nerve net allows Hydra to respond to environmental stimuli. It includes sensory neurons that can detect light (photoreceptors) and touch-sensitive neurons located in the tentacles.

5. **Conclusion**:
- Since Hydra does not possess a centralized brain or a structured CNS or PNS, the correct answer to the question is that Hydra's neural organization is comprised of a network of neurons.

### Final Answer:
- The neural organization in Hydra is comprised of a network of neurons.

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