Question

What type of neuron is characterized by having a single dendrite and a single axon?

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

Answer 1

A bipolar neuron is characterized by a single dendrite and a single axon. It is exemplified by retinal bipolar cells in the visual system, unlike multipolar neurons that have multiple dendrites or pseudounipolar neurons that have a single process dividing into two branches.

Step-by-step explanation:

The type of neuron characterized by having a single dendrite and a single axon is the bipolar neuron. Bipolar neurons have one axon and one dendrite extending from the cell body.

An example is a retinal bipolar cell, which plays a role in visual processing by receiving signals from photoreceptor cells and transmitting them to ganglion cells that carry the information to the brain.

Multipolar neurons, on the other hand, are the most common type of neuron and have one axon and multiple dendrites. Unipolar neurons, also known as pseudounipolar neurons, have a single process that branches into two.

It is important to note that in humans, what are often called unipolar neurons are more accurately termed pseudounipolar cells, as they involve a branching that leads to dendrites at one end and synaptic connections at the other. Sensory neurons, which are typically unipolar in invertebrates, are usually pseudounipolar in humans.

Answer 2

A neuron with a single dendrite and a single axon is a bipolar neuron. These are found in the retina and are critical for transmitting visual information to the brain. Other types of neurons include multipolar, unipolar, and pseudounipolar, each with distinct structures and functions. Option B. Bipolar neuron is the correct answer.

Step-by-step explanation:

The type of neuron characterized by having a single dendrite and a single axon is known as a bipolar neuron. These neurons are less common compared to other types and can be found in specific areas of the body such as the retina.

In the retina, for instance, the bipolar neuron plays a critical role in the visual pathway; it receives signals from photoreceptor cells sensitive to light and transmits these signals to ganglion cells, which then relay the information to the brain.

Multipolar neurons, on the other hand, contain one axon and multiple dendrites and are the most common neural type within the central nervous system. Unipolar neurons have only one structure that extends away from the soma and are commonly found in insects.

Finally, pseudounipolar neurons, which are primarily sensory neurons, have characteristics of both unipolar and bipolar neurons, with a single process that branches into two distinct structures.