NB1-1 - Organization of the Nervous System 1 and DLAs

Question 1

What predominates in white and grey matter?

Answer 1

Grey Matter - mostly cell bodies, aka nuclei, and unmyelinated axons

White Matter - mostly myelinated axons, aka tracts

Question 2

What are the 5 major parts of the brain and the alternate names each part has?

Answer 2

1. Telencephalon, aka endbrain, aka cerebrum
2. Diencephalon, aka interbrain
3. Mesencephalon, aka midbrain
4. Metencephalon, aka pons + cerebellum
5. Myelencephalon, aka medulla oblongata

Question 3

What parts of the brain make up the forebrain, midbrain, and hindbrain? What are the other names for the forebrain, midbrain, and hindbrain>

Answer 3

• The forebrain, aka prosencephalon, consists of the telencephalon (cerebrum/endbrain) and diencephalon (interbrain)
• The midbrain (no other name besides mesencephalon) consists of the mesencephalon
• The hindbrain, aka rhombencephalon, consists of the metencephalon (pons + cerebellum) and myelenchephalon (medulla oblongata)

Question 4

What parts of the briain compose the brainstem? What is the brainstem also known as?

Answer 4

The midbrain (mesencephalon), pons (part of metencephalon), and medulla oblongata (myelencephalon)

Brainstem is also known as the bulbus

Question 5

From which structures do the five main areas of the brain arise?

Answer 5

• Telencephalon arises from the rostral forebrain (prosencephalon)
• Diencephalon arises from the caudal forebrain (prosencephalon)
• Mesencephalon arises from the midbrain (mesencephalon)
• Metencephalon arises from the hindbrain (rhobencephalon)
• Myelencephalon arises from the hindbrain (rhombencephalon)

Question 6

List the major structures found within the telencephalon.

Answer 6

Cerbrum

Basal Ganglia

Hippocampus

Amygdala

Lateral Ventricles

Olfactory Nerves (I)

Question 7

List the major structures found within the diencephalon

Answer 7

Thalamus

Hypothalamus

Pituitary

Subthalamus

Epithalamus

Third Ventricle and Cerebral Aqueduct

Optic Nerve (II)

Question 8

List the major structures found within the mesencephalon.

Answer 8

Tegmentum (floor)

Tectum (roof)

Cerebral aqueduct

Oculomotor nerve (III)

Trochlear nerve (IV)

Question 9

List the major structures found within the metencephalon

Answer 9

• Pons
• Cerebellum
• Rorstral Fourth Ventricle
• Trigeminal Nerve (V)
• Abducens Nerve (VI)
• Facial Nerve (VII)
• Vestibulocochlear Nerve(VIII)

Question 10

List the major structures found within the myelencephalon

Answer 10

Medulla Oblongata

Caudal Fourth Ventricle

Glossopharyngeal Nerve (IX)

Vagus Nerve (X)

Spinal Accessory Nerve (XI)

Hypoglossal Nerve (XII)

Question 11

Answer 11

Question 12

Describe the locations of the enlargements and narrowings of the spinal cord and why these enlargements and narrowings exist.

Answer 12

Cervical enlargement (C7-C8), thoracic narrowing, lumbar enlargement (L5), sacral and coccygeal narrowing.

The cervical and lumbar enlargements exist because the nerve fibers that control the arms and legs exit here. This requires more cell bodies, thus more grey matter. The thoracic, sacral, and coccygeal segments primarily control the thorax, abdomen, and pelvis which doesn’t require as much grey matter

Question 13

Answer 13

B

Question 14

What is the name for the boundary between the CNS and PNS? What major change occurs at this boundary?

Answer 14

Redlich-Obersteiner’s Zone

The myelin forming cells switch from oligodendrocytes in the CNS to Schwann cells in the PNS.

Question 15

Answer 15

Question 16

Answer 16

E

Question 17

Answer 17

Question 18

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Question 19

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Question 20

Answer 20

Question 21

What are the other names for an anatomical horizontal plane?

Answer 21

Axial and transverse

Question 22

When looking at a transverse or coronal image of the brain, from which direction are you viewing it? From above or below? From in front or behind? What’s and easy way to remember this?

Answer 22

You are looking at it from below or in front, respectively. When visually assessing a patient, you stand at the foot of the bed which means you are assessing them from below and in front of them. Radiographs are the same way

Question 23

Answer 23

Question 24

Answer 24