Which one of the following is present in embryonic stage of vertebrates ?

Options

A. Multipolar neuron
B. Bipolar neuron
C. Pseudounipolar neuron
D. Unipolar neuron

Answer

To solve the question "Which one of the following is present in the embryonic stage of vertebrates?" we will analyze the types of neurons mentioned: multipolar, bipolar, pseudo-unipolar, and unipolar neurons.

### Step-by-Step Solution:

1. **Understanding Neurons**: Neurons are specialized cells in the nervous system responsible for receiving and transmitting signals. They consist of three main parts: dendrites, cell body, and axon.

2. **Types of Neurons**:
- **Multipolar Neurons**: These neurons have one axon and multiple dendrites. They are primarily found in the cerebral cortex and are not present in the embryonic stage of vertebrates.

- **Bipolar Neurons**: These consist of one axon and one dendrite. They are mainly located in the retina and are also not present in the embryonic stage.

- **Pseudo-Unipolar Neurons**: These neurons have a single process that splits into two branches. They are typically found in sensory ganglia but are not specifically mentioned as present in the embryonic stage.

- **Unipolar Neurons**: These neurons have a single axon and are characterized by having their cell body off to one side. They are typically found in the embryonic stage of vertebrates.

3. **Conclusion**: Based on the analysis of the types of neurons, the correct answer to the question is **unipolar neurons**, as they are the only type mentioned that is present during the embryonic stage of vertebrates.

### Final Answer:
**Unipolar neurons** are present in the embryonic stage of vertebrates.

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