The spinal cord and others Final

Question 1

The spinal cord

Answer 1

• Elongated almost cylindrical part of the nervous system which lies in the upper 2/3 of the vertebral canal.

Question 2

How long is the spinal cord and where does it start and end.

Answer 2

• 45 cm in length
• Extends from atlas to the lower boarder of the 1st lumbar.

Question 3

what name is given to the extremity where the spinal cord ends in the lumbar region.

Answer 3

Conus medullaris

Question 4

How many pairs of nerves arise from the spinal cord.

Answer 4

• 31 pairs of nerves
• Each nerve rises by two roots, an anterior root and posterior root

Question 5

another name of anterior root

Answer 5

ventral root

Question 6

THE ANTERIOR ROOT

Answer 6

• Contains the efferent fibres of the autonomic nervous system.

Question 6

another name of posterior root

Answer 6

dorsal root

Question 6

The posterior root

Answer 6

• Contains sensory fibres passing into the spinal cord.

Question 7

Arrangement of spinal nerves in the spinal cord.

Answer 7

8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal

Question 8

Composition of the spinal cord.

Answer 8

• The spinal cord is composed of
• white matter,
• grey matter
• neuroglial tissue.

Question 9

The grey matter of spinal cord

Answer 9

• Lies centrally
• On the transverse of the cord it appears to have an H arrangement
• The limbs of the H are symmetrical and each has an exterior and posterior horn.

Question 10

The anterior horn of the grey matter.

Answer 10

contains nerve cells the axons of which form the motor fibres of the anterior nerve roots

Question 11

what forms the motor fibres

Answer 11

axons

Question 12

The posterior horn of the spinal cord

Answer 12

contains nerve cells of the connector type

Question 13

How is synapse formed by posterior root fibres.

Answer 13

• The posterior horn of the spinal cord contain nerve cells of connector type which form the synapse

Question 14

The white matter of the spinal cord

Answer 14

• Surrounds the grey matter
• Divided by the limbs of grey matter into 3 columns

Question 15

Columns of the white matter of the spinal cord.

Answer 15

• Posterior
• Lateral
• Anterior

Question 16

Types of fibres within the white matter

Answer 16

• Ascending fibres
• Descending fibres
• Intersegmental fibres

Question 17

Ascending fibres

Answer 17

Carry sensory impulses to the brain

Question 18

Descending fibres

Answer 18

carry motor impulses from the brain to the cells of the anterior horn of the spinal cord.

Question 19

Intersegmental fibres

Answer 19

carry impulses from one level
of the cord to another

Question 20

The sensory pathways

Answer 20

• Sensory impulses enter the spinal cord in the posterior nerve roots
• Sensations that enter the spinal cord in the posterior never roots are of pain, temp, light touch, pressure

Question 21

Motor pathways

Answer 21

• Motor impulses which produces contractions of voluntary muscles
• Initiated in the cells of the motor area of the cerebral cortex
• They finally form synapses with anterior horn cells at the level of the cord for which they are destined

Question 22

Reflexes

Answer 22

reflexes are automatic motor responses to sensory stimuli and they occur without the direct involvement of the
brain.