Peripheral Nervous System

Question 1

What does the PNS do?

Answer 1

Transmits information to and from the brain and spinal cord

Question 2

Axons of the somatic component go to?

Answer 2

Sensory and motor axons associated with activity in the muscles, the joins and the skin

Question 3

Axons of the visceral component (autonomic NS) go to?

Answer 3

Axons carrying nerve impulses to the glands, organs and blood vessels

Question 4

Incoming (afferent) axons are located in which root?

Answer 4

Dorsal (posterior) root

Question 5

Outgoing (efferent) axons are located in which root?

Answer 5

Central (anterior) root

Question 6

What is a ganglion?

Answer 6

A swelling on the dorsal root is called the dorsal root ganglion which is where all the cell bodies of sensory neurons sit

Question 7

What is a motor unit?

Answer 7

One lower motor neuron and all the muscle fibres it inner ages

Question 8

What 2 mechanisms controls the strength of a muscle contraction?

Answer 8

Frequency and recruitment

Question 9

How many nerve plexus’ are in the body?

Answer 9

4

Question 10

What are the 3 types of reception found in the body?

Answer 10

Cutaneous receptors, proprioceptors, nociceptors

Question 11

What are the 2 types of cutaneous receptors? What do they respond to?

Answer 11

Mechanoreceptors - respond to mechanical forces such as touch, pressure, vibration and stretch
Thermoreceptors - respond to temperature
Nociceptors - respond to noxious stimuli and result in the sensation of pain

Question 12

What is a dermatome?

Answer 12

An area of skin supplied by all the sensory nerve fibres of one spinal nerve

Question 13

What are dermatome maps used for?

Answer 13

To determine the source of pain by identifying the area of skin innervated by a specific spinal nerve

Question 14

What does it mean that peripheral nerves are ‘mixed’ nerves?

Answer 14

They contain sensory (afferent) and motor (efferent) neurons

Question 15

What are the 12 cranial nerves and what are they associated to?

Answer 15

Learn the table

Question 16

What are the 2 divisions of the ANS?

Answer 16

Sympathetic and Parasympathetic

Question 17

Which system is the ‘fight or flight’ system?

Answer 17

Sympathetic

Question 18

Which system is the ‘rest and digest’ system?

Answer 18

Parasympathetic

Question 19

ANS nerve fibres are larger or smaller than those of the somatic nervous system?

Answer 19

Smaller

Question 20

What are some actions of the sympathetic nervous system?

Answer 20

Increases heartbeat, regulates blood, increase ventilation, raise glucose in blood, dilate pupils, stimulate sweat glands

Question 21

What is the chain of ganglion?

Answer 21

The sympathetic nervous system structure is in a chain. Each ganglion is linked to the next from the base of the skull to the coccyx.

Question 22

What are some of the actions of the parasympathetic nervous system?

Answer 22

Decreases heart rate, slows breathing, constricts pupils, stimulates digestion

Question 23

Where are the ganglion of the parasympathetic nervous system?

Answer 23

Near the structure supplied by the nerve. Eg. the heart.