Histology Testbank: Nervous System 5a

Instructions: For each histology question, pick the one best answer. This histology test bank is also useful for the histology questions on the USMLE (USMLE step 1).

1.
Which of the following is found in the cerebellum?
a. Schwann cells
b. Basket cells
c. Ganglion
d. Neuroglia
e. Satellite cells

Answer: b

Schwann cells are responsible for the myelination of neurons in the peripheral nervous system. Basket cells are a type of neuron seen in the cerebellum. A ganglion is a collection of nerve cell bodies outside of the CNS. Neuroglia are the supporting cells in the central nervous system Sometimes, neuroglia called glial cells or glia. Satellite cells are found in the ganglia of the peripheral nervous system.

2.
What are neurons in the retina?
a. Unipolar
b. Pseudounipolar
c. Bipolar
d. Multipolar
e. Both a and b

Answer: c

The neurons in the retina are bipolar.

Neurons can be classified based on the number of axons and dendrites stemming off of the cell body. A unipolar neuron has one process which branches off of it This process then immediately divides into two. Thus, a unipolar neuron is sometimes also called a pseudounipolar neuron. Sensory neurons are unipolar.

A bipolar neuron has two process that branch from it: an axon and a dendrite. Bipolar neurons are not very common and are found in some of the organs for special senses. Bipolar neurons are found in the retina, inner ear, and the region of the nose involved with smell.

Multipolar neurons have one axon and many (at least two) dendrites that branch off of it. Most neurons are multipolar. Motor neurons and interneurons are multipolar.

3.
What are the basophilic clusters of ribosomes and rough endoplasmic reticulum seen in neurons called?
a. Ganglion
b. Perikaryon
c. Astrocyte
d. Nissl
e. Terminal bouton

Answer: d

A ganglion is a collection of neuron cell bodies outside of the central nervous system. The cell body of a neuron is called a perikaryon or soma. An astrocyte is a supporting cell seen in the central nervous system. The basophilic clusters of ribosomes and rough endoplasmic seen in neuron cell bodies is called Nissl, Nissl bodies or Nissl substance. The terminal bouton is the end portion of an axon. It is also called an axon terminal or end bulb. The terminal bouton will be associated with another neuron in a synapse.

4.
All of the following are properties of neurons, except:
a. High metabolic rate
b. Longevity
c. Specialized for conduction
d. High mitotic rate
e. Limited ability for oxygen deprivation

Answer: d

Neurons do not divide; therefore they do not have a high mitotic rate.

Neurons have a high metabolic rate. They are unable to survive long without oxygen. They have an extremely long longevity, lasting a lifetime. Neurons are specialize for conduction. They send signals via a nervous impulse.

5.
Which type of neuron is also called an internuncial neuron?
a. Sensory neurons
b. Motor neurons
c. Interneurons
d. Both a and b
e. All of the above

Answer: c

Interneurons are also called internuncial neurons.

6.
What is white matter?
a. Meninges
b. Myelinated nerve fibers
c. Cell bodies
d. Nodes of Ranvier
e. Neurofilaments

Answer: b

A ganglion is a collection of nerve cell bodies outside of the central nervous system. White matter is myelinated nerve fibers. Gray matter is essentially neuron cell bodies. Nodes of Ranvier are the gaps that occur in the myelin sheath. Neurofilaments are a type of intermediate filaments seen in neurons.

7.
What is another term for the cell body of a neuron?
a. Tracts
b. Islets
c. Soma
d. Cortex
e. Nuclei

Answer: c

A group of fibers traveling together to a destination is a tract. Islets of Langerhans are seen in the pancreas. Soma is another term for a neuron cell body. The outer part of the brain is gray matter called the cortex. The conglomerations of gray matter deep within the cerebrum and cerebellum are called nuclei.

8.
What is the covering of a nerve fiber?
a. Neurium
b. Perineurium
c. Epineurium
d. Endoneurium
e. None of the above

Answer: d

The endoneurium surrounds a nerve fiber. The perineurium surrounds a bundle of
nerve fibers. The epineurium surrounds a nerve.

9.
Which of the following is the CNS macrophage?
a. Astrocytes
b. Ependymal cells
c. Oligodendrocytes
d. Microglia
e. Schwann cells

Answer: d

Neuroglia are the supporting cells of the central nervous system. Sometimes, neuroglia called glial cells or glia. Astrocytes, ependymal cells, oligodendrocytes, and microglia are all neuroglia.

Of the neuroglia cells, astrocytes are the most abundant and the largest. These are star shaped cells involved in the blood brain barrier.

Ependymal cells line the ventricles and spinal canal.

Oligodendrocytes form myelin in the central nervous system.

Microglia are the central nervous system macrophages.

Schwann cells are seen in the peripheral nervous system and are not considered neuroglia. Schwann cells are responsible for the myelination of neurons in the peripheral nervous system.

10.
Which of the following is found in the peripheral nervous system?
a. Astrocytes
b. Ependymal cells
c. Oligodendrocytes
d. Microglia
e. Schwann cells

Answer: e

Neuroglia are the supporting cells of the central nervous system. Sometimes, neuroglia called glial cells or glia. Astrocytes, ependymal cells, oligodendrocytes, and microglia are all neuroglia.

Of the neuroglia cells, astrocytes are the most abundant and the largest. These are star shaped cells involved in the blood brain barrier.

Ependymal cells line the ventricles and spinal canal.

Oligodendrocytes form myelin in the central nervous system.

Microglia are the central nervous system macrophages.

Schwann cells are seen in the peripheral nervous system and are not considered neuroglia. Schwann cells are responsible for the myelination of neurons in the peripheral nervous system.