Anatomy Week 9 - Anatomy of the spinal cord

Question 1

What age does the spinal cord finish growing and what age does the vertebral column finish growing?

Answer 1

Spinal cord finishes growing at age 4.

Vertebral column finishes growing at age 14 - 18.

Question 2

How many segments of the spinal cord are there? And how many are in each spinal area?

Answer 2

31 pairs
Cervical: 8
Thoracic: 12
Lumbar: 5
Sacral: 5
Coccygeal: 1
Dorsal and ventral roots enter and leave the vertebral column through the intervertebral foramen.

Question 3

What two pats of the spinal cord show enlargements to accommodate for innervation of the upper and lower limbs?

Answer 3

Cervical level (upper limbs) : C3 - T1.

Lumbosacral level (lower limbs): L1 - S2.

Question 4

A stand of fibrous tissue, formed by meninges, that extends from the tip of the conus medullaris all the way 1st coccygeal vertebra is called?

Answer 4

Filum terminale.

Question 5

A collection of spinal nerve roots distal to the Conus medullaris is called?

Answer 5

Cauda equina.

Question 6

What are the 3 meningeal layers that cover the spinal cord?

Answer 6

1. Dura mater
2. Arachnoid mater
3. Pia mater

Question 7

What separates the dura mater from the periosteum of the vertebral canal?

Answer 7

Epidural space.

Question 8

What is the space between the arachnoid and pia mater called? And what type of fluid is it filled with?

Answer 8

Subarachnoid space, filled with cerebrospinal fluid.

Question 9

An internal structure of the spinal cord that is in the periphery and contains myelinated and unmyelinated nerve fibers is called?

Answer 9

White matter.

Question 10

An internal structure of the spinal cord that contains cell bodies is called?

Answer 10

Gray matter.

Question 11

Surrounding the tiny central canal filled with cerebrospinal fluid (CSF) is a single layer of cells called?

Answer 11

The ependymal layer.

Question 12

Surrounding the ependymal layer is grey matter that is shaped like a …?

Answer 12

Butterfly.

Question 13

The two ‘wings’ are connected across the midline by the…?

Answer 13

Dorsal gray commissure.

Question 14

What three horns is the grey matter divided into?

Answer 14

1. Dorsal horn
2. Lateral horn
3. Ventral horn

Question 15

True of false:
At the lower levels, the ratio between gray matter and white matter is greater than in higher levels, because lower levels contain less ascending and descending nerve fibers.

Answer 15

True.

Question 16

What three columns is the white matter divided into?

Answer 16

1. Dorsal column
2. Lateral column
3. Ventral column

Question 17

A tract that carries sensory information from the peripheral nerves to the brain is called the?

Answer 17

Ascending tract.

Question 18

What are the three major pathways of the Ascending tract?

Answer 18

1. Dorsal column
2. Spinothalamic tract
3. Spinocerebellar tract

Question 19

The column that carries information related to fine touch, vibration and proprioception is called?

Answer 19

Dorsal column.

Question 20

The tract that carries pain, temperature and crude touch is called?

Answer 20

Spinothalamic tract.

Question 21

The tract that carries unconscious proprioception to the cerebellum for motor coordination is called?

Answer 21

Spinocerebellar tract.

Question 22

The tract responsible for transmitting motor commands from the brain to the peripheral nervous system and controlling voluntary movement, muscle tone, reflexes, and autonomic functions is called?

Answer 22

The Descending tract.

Question 23

The horn that is found at all spinal cord levels
and is comprised of sensory nuclei that receive and process incoming somatosensory information is called?

Answer 23

The dorsal horn.

Question 24

The horn that comprises autonomic neurons innervating visceral and pelvic organs is called?

Answer 24

Lateral horn.

Question 25

The horn comprises motor neurons that innervate skeletal muscle is called?

Answer 25

Ventral horn.

Question 26

The axons originating from the primary sensory dorsal root ganglion cells are called?

Answer 26

Dorsal root fibers.

Question 27

The .... receives information from the skin, skeletal muscle and joints to be relayed to the spinal cord.

Answer 27

Dorsal root ganglia.

Question 28

Roots that originate from the anterior (ventral) horn of the spinal cord are called?

Answer 28

Ventral roots.

Question 29

Roots that contain axons of motor neurons that send signals to skeletal muscles (somatic motor) and autonomic targets (visceral motor) are called?

Answer 29

Ventral roots.

Question 30

Where is the spinal cord located?

Answer 30

Vertebral canal.

Question 31

The union of dorsal and ventral roots form?

Answer 31

Spinal nerves.

Question 32

After exiting vertebral column, each spinal nerve splits into branches, called?

Answer 32

Rami.

Question 33

Ramus that innervate the skin and muscles of the back is called?

Answer 33

Dorsal primary ramus.

Question 34

Ramus that innervates the ventral lateral muscles and skin of the trunk, extremities and visceral organs is called?

Answer 34

Ventral primary ramus.

Question 35

Areas of the skin that is connected to a specific spinal nerve is called?

Answer 35

Dermatomes.

Question 36

Specific muscles that are supplied by a specific spinal nerve is called?

Answer 36

Myotomes.