The Peripheral Nervous System

Question 1

Name the three parts of a neuron

Answer 1

Axon, dendrite, cell body

Question 2

What carries information to the cell body?

Answer 2

Dendrites

Question 3

What carries information from the cell body?

Answer 3

Axon

Question 4

Plaques of demyelination and axon loss throughout the central (but not peripheral) nervous system

Answer 4

Multiple sclerosis

Question 5

What structure protects the spinal cord?

Answer 5

The spinal cord is protected by the bones of the spinal column, the vertebrae

Question 6

At what vertebral level does the spinal cord end in adults and children?

Answer 6

The spinal cord ends at L1 in adults and L3 in children

Question 7

What does the spinal cord consist of?

Answer 7

The spinal cord consists of neurons which form white matter tracts ascending to and descending from the brain, and some forming relays within the grey matter of the spinal cord

Question 8

What is the vertebral canal?

Answer 8

The lining up of vertebral foramen (open space) in the vertebral column

Question 9

Where do nerves enter the body?

Answer 9

Dorsal roots or dorsal horn

Question 10

What is the outer section of a neuron formed from?

Answer 10

White matter

Question 11

What is the inner section of a neuron formed from?

Answer 11

Grey matter

Question 12

Nerves that travel to the CNS are…?

Answer 12

Afferent

Question 13

Nerves that travel from the CNS are…?

Answer 13

Efferent

Question 14

Subconscious control of our bodies, generally innervating smooth muscle of tissues or glands. It is involved with actions such as temperature control (via sweating and vasomotor), continence, secretions and gastric motility.

Answer 14

Autonomic nervous system

Question 15

Difference between sympathetic and parasympathetic nervous system

Answer 15

In general, the sympathetic system prepares the body for intense physical activity, whilst the parasympathetic system relaxes the body and inhibits high energy functions

Question 16

Which nervous system is stimulated to increase heart rate?

Answer 16

Sympathetic

Question 17

Which nervous system is stimulated to increase salivary gland saliva secretion?

Answer 17

Parasympathetic

Question 18

Location of sympathetic neurons and their ganglia

Answer 18

Thoracic or lumbar spinal cord, ganglia in chains far from target organ

Question 19

Location of parasympathetic neurons and their ganglia

Answer 19

Cranial nerves or lumbo-sacral spinal cord, ganglia are close to target organ

Question 20

What is the somatic nervous system responsible for?

Answer 20

The somatic nervous system is responsible for conscious control of the body and associated sensory functions

Question 21

What are the four types of somatosensation?

Answer 21

Touch (pressure), pain (nociception), temperature (specifically changes in temperature), proprioception (location of the body in space, spacial awareness)

Question 22

What do somatic efferent nerves innervate?

Answer 22

Somatic efferent neurons innervate skeletal muscle

Question 23

What are the two types of somatic neuron?

Answer 23

Spinal nerves and cranial nerves

Question 24

The origin of nerve signals initiating movement

Answer 24

(Brain) Precentral gyrus

Question 25

Mediator of message from brain to skeletal muscles

Answer 25

(Cross Section of Spinal Cord) Corticospinal tract

Question 26

The messenger cell that carries the command to contract muscles

Answer 26

Axon

Question 27

The messenger axon cell tells muscle cells to contract at this intersection

Answer 27

Neuromuscular junction

Question 28

Neurons from which nervous systems are carried in spinal nerves?

Answer 28

The spinal nerves are a part of the peripheral nervous system and carry both somatic and autonomic neurons

Question 29

What is a dermatome?

Answer 29

Area of skin supplied by sensory afferents from one spinal nerve

Question 30

What is a myotome?

Answer 30

A group of muscles supplied by motor efferents and sensory afferents from one spinal nerve

Question 31

What is a plexus?

Answer 31

A network of interconnecting nerves, nerves form groupings in the plexus and leave as peripheral nerves

Question 32

What are the special senses?

Answer 32

Taste, smell, sight, hearing and balance

Question 33

List the cranial nerves

Answer 33

Olfactory, optic, oculomotor, trochlear, trigeminal, abducent, facial, vestibulocochlear, glossopharyngeal, vagus, accessory and hypoglossal nerves

Question 34

CN I Olfactory

Answer 34

Special sense, afferent from nasal mucosa carries information related to smell

Question 35

CN II Optic

Answer 35

Special sense, afferent for vision from the retina

Question 36

CN III Oculomotor

Answer 36

Controls eye movement and pupil constriction

Question 37

CN IV Trochlear

Answer 37

Motor to one muscle that moves eye

Question 38

CN V Trigleminal

Answer 38

Afferent from surface of face, senses touch, motor efferent to muscles of mastication (chewing)

Question 39

CV VI Abducent

Answer 39

Somatic: motor efferent to one muscle of the eye

Question 40

CN VII Facial

Answer 40

Special sense: taste from tongue. Somatic: motor to muscles of facial expression. Autonomic: Motor efferent to glands in saliva secretion

Question 41

CN VIII Vestibulocochlear

Answer 41

Special sense: hearing and balance

Question 42

CN IX Glossopharyngeal

Answer 42

Special sense: taste. Somatic: motor efferent to swallowing and afferent sensation from external ear. Autonomic: secretomotor to one salivary gland and afferent sensation from carotid body and sinus

Question 43

CN X Vagus

Answer 43

Somatic: motor muscles pharynx, larynx and palate. Autonomic: parasympathetic innervation of smooth muscle in trachea, bronchi, HI tract and cardiac muscle

Question 44

CN XI Accessory

Answer 44

Somatic: motor to soft palate pharynx and to two big muscles in the neck

Question 45

CN XII Hypoglossal

Answer 45

Somatic: motor to muscles of the tongue