Question

Pseudo-unipolar neurons occur in
A. Retina
B. Dorsal ganglion
C. Ventral root of spinal nerve
D. Nerve Nuclei

Answer 1

Hint: The nerve cell or neuron may be unipolar, bipolar or multipolar. The neuron may be true or pseudo (false). The pseudo-unipolar neuron is the part of the peripheral nervous system.

Complete answer:
Neurons or nerve cells are the basic units of the nervous system which send and receive signals for the functioning of organisms. The nerve cells or neurons may be unipolar, bipolar or multipolar. The neurons may be true or pseudo (false). The unipolar neurons are those which have one axon arising from the cell body. The pseudo-unipolar neurons are those which have an axon that bifurcates into two separate branches resulting in a distal process and proximal process. Thus, they are the pseudo-unipolar neurons.

Pseudo-unipolar neurons are afferent or sensory neurons of the peripheral nervous system.
The axons of dorsal ganglion neurons are the sensory or afferent neurons. These neurons relay sensory neural messages from the periphery to the brain and spinal cord which are included in the central nervous system.

Hence, the correct answer is option (B).

Additional information:
Types of Neurons on the basis of number of Axon and Dendrites
• Multipolar neurons: These possess a cell body with one axon and two or more dendrites.
• Bipolar neurons: These possess a cell body with one axon and one dendrite.
• Unipolar neurons: These possess a cell body with one axon only.

Note: Dorsal ganglions are considered pseudo-unipolar neurons, with one axon that splits into two separate branches resulting in a distal process and proximal process. These neurons relay sensory neural messages from the periphery to the central nervous system.