Somatic NS

Question 1

What is the functioning unit for the nervous system?

Answer 1

Neurons

Question 2

Name the three main parts of a neuron.

Answer 2

Axon, cell body, dendrite

Question 3

What are the three major types of neuron?

Answer 3

Bipolar
Multipolar
Pseudounipolar.

Question 4

What are the four main types of cells found in the CNS?

Answer 4

Astrocytes, microglial cells, ependymal cells, and oligodendrocytes.

Question 5

What is myelin?

Answer 5

Protein and lipid substance

Question 6

What does a myelin sheath do?

Answer 6

Increase velocity of impulse conduction (insulation)

Question 7

Why are peripheral nerves resilient?

Answer 7

Protected by three layers of connective tissue coverings

Question 8

What is a dermatome?

Answer 8

Area of skin supplied by a single spinal nerve

Question 9

What is a myosome?

Answer 9

Part of muscle supplied by a single spinal nerve

Question 10

What is the clinical relevance of dermatomes and myotomes?

Answer 10

Useful to test motor or sensory loss of one or more spinal nerves/segments by testing joint movements or an area of skin in neurological disorders.

Question 11

What is a motor end plate?

Answer 11

A neuromuscular junction

Question 12

RECAP- what makes up the CNS?

Answer 12

Brain and spinal cord

Question 13

RECAP- what makes up the PNS?

Answer 13

Cranial nerves, Spinal nerves and peripheral ganglia

Question 14

How many pairs of cranial nerves are there?

Answer 14

12

Question 15

How many pairs of spinal nerves are there?

Answer 15

31

Question 16

What are the two components of the somatic NS?

Answer 16

Motor and sensory

Question 17

What is controlled by the somatic motor system?

Answer 17

Voluntary control
Skeletal muscle

Question 18

What is controlled by somatic sensory system?

Answer 18

Pain/ touch/temperature/ proprioception etc., skin

Question 19

What does a somatic motor fibre do?

Answer 19

Regulates voluntary control of body movements via skeletal muscle.

Question 20

What do somatic sensory fibres do?

Answer 20

Transmits general sensation to the CNS

Question 21

What would happen if there was damage to the anterior/ventral root?

Answer 21

Motor loss

Question 22

What would happen if there was damage to the posterior/dorsal root?

Answer 22

Sensory loss

Question 23

What would happen if there was damage to ventral ramus>

Answer 23

Motor and sensory loss of anterolateral trunk and limbs

Question 24

What would happen if there was damage to the dorsal ramus?

Answer 24

Motor and sensory loss at the back

Question 25

What do spinal nerves also carry?

Answer 25

Sympathetic fibres

Question 26

Where does the spinal nerve exit through?

Answer 26

Intervertebral foramen

Question 27

What is a Somatic Reflex Arc?

Answer 27

Sensory detection
Interpretation of sensory input in the CNS
Motor response

Question 28

What is the function of the muscles at the back of the arm and forearm?

Answer 28

Back of arm- extensors of the elbow
Forearm- extensors of the wrist

Question 29

Which nerve supplies the muscles at the back of the arm and forearm?

Answer 29

Radial nerve

Question 30

What does damage to lower motor neuron cell bodies or their peripheral axons result in?

Answer 30

Paralysis
Weakness of affected muscles