Spinal nerve - Week 3

Question 1

Which type of neurons do the spinal nerves contain?

Answer 1

A mixture of both motor and sensory neurons meet in the spinal nerve

Question 2

How many pairs of spinal nerves and how many in each region?

Answer 2

31
Cervical - 8
Thoracic - 12
Lumbar - 5
Sacral - 5
Coccygeal - 1

Question 3

What is the highest pair of spinal nerves and where does it exit?

Answer 3

C1 and it exits above its corresponding vertebral body (atlas)

Question 4

The path a motor nerve impulse follows starting at the spinal cord

Answer 4

From CNS through the ventral grey horn out the ventral rootlets, ventral root, spinal nerve (containing both ventral and dorsal), ventral primary ramus, neuromuscular junction, effector muscle

Question 5

Which areas of the body does the ventral primary rami innervate?

Answer 5

Muscles and skin of the antero-lateral parts of the trunk and the limbs

Question 6

Which areas of the body does the dorsal primary ramus innervate?

Answer 6

Posterior aspect of the body as well as the deep intrinsic back muscles

Question 7

What is a spinal reflex?

Answer 7

It is the most basic function of the spinal nerve. This bypasses the brain, and works only in between afferent and efferent nerves in the spinal cord.

Question 8

Example of a spinal reflex

Answer 8

If you touch something is hot, you will activate the flexor response which tells your muscle to contract and withdraw the point of contact away from the hot surface.

Question 9

Name a structure the dorsal ramus supplies

Answer 9

Posterior skin and deep back muscles

Question 10

Name a structure the ventral ramus supplies

Answer 10

Anterior and lateral skin