Peripheral Nervous System

Question 1

Somatic afferent nerves convey information from

Answer 1

Skin, skeletal muscle and joints

Question 2

Somatic afferent nerves convey information to

Answer 2

Skeletal muscles

Question 3

What is a dermatome

Answer 3

An area of skin that is supplied by single spinal nerve

Question 4

What is a myotome

Answer 4

Group of muscles innervate by a single spinal nerve

Question 5

How can myotomes be tested

Answer 5

Most individual muscles of the body are innervate by more than one spinal-cord level so the evaluation of myotomes is usually accompanied by testing movements of joints or muscle groups

Question 6

How can the dermatome be tested

Answer 6

There is an overlap between the distributions of dermatomes but usually a specific region within each dermatome can be identified as an area supplied by single spinal-cord level
Testing touch in the autonomous zones in a conscious patient can be used to localised lesions in a specific spinal nerve or to a specific level of the spinal-cord

Question 7

What is the viscera

Answer 7

Thoracic
Abdominal
Pelvic

Question 8

Where do you sympathetic efferent nerves innervate

Answer 8

Viscera ( organs) and periphery( vascular urge and sweat glands)

Question 9

Where do parasympathetic nerves innervate

Answer 9

Viscera only

Question 10

What is a ganglion

Answer 10

A collection of cell bodies outside the central nervous system

Question 11

What is the nucleus

Answer 11

A collection of cell bodies inside the central nervous system

Question 12

What is a plexus

Answer 12

A network of interconnecting nerves

Question 13

All afferent fibres have a cell bodies in the

Answer 13

Spinal ganglia

Question 14

Visceral efferent fibres synapse in the

Answer 14

Peripheral ganglion

Question 15

What is an axon covered in

Answer 15

Endoneurium

Question 16

What does a fascicle consistent of

Answer 16

Many axons

Question 17

What is the fascicle covered in

Answer 17

Perineurium

Question 18

Many fascicles form a

Answer 18

Nerve

Question 19

What is a nerve covered in

Answer 19

Epineurium

Question 20

What are the two classification system of peripheral nerves

Answer 20

Conduction velocity
Axonal diameter( sensory only)

Question 21

Classification system based on conduction velocity

Answer 21

Uses letters A,B and C with A being fastest

Question 22

Classification system based on axonal diameter

Answer 22

Uses Roman numerals I- IV with I being the largest diameter

Question 23

What are Exteroceptors

Answer 23

To text pain touch temperature and pressure

Question 24

What are proprioceptors

Answer 24

Detect movement and joint position.
They can be found in muscle spindles - detect changes in muscles length

They can be found in golgi tendon organs- detect changes in tension in tendons

They can be found in joint receptors - found in joint capsules and detect start and end of movement

Question 25

What are enterorepetors

Answer 25

Detect movement through gut and blood pH

Question 26

What is an example of external sensory receptors

Answer 26

Exteroceptors

Question 27

What is an example of internal sensory receptors

Answer 27

Proproceptors and enteroceptors

Question 28

Chemoreceptors

Answer 28

Detect molecules which binds to receptor , for example in olfactory bulb

Question 29

What are photoreceptors

Answer 29

Detect light in the retina

Question 30

Was are thermoreceptors

Answer 30

Detect temperature in the skin

Question 31

What are mechanoreceptors

Answer 31

Mechanical opening of iron channel for example touch receptors in the skin

Question 32

Nociceptors

Answer 32

Detect tissue damage, interpreted as pain

Question 33

What is the neuromuscular junction

Answer 33

Specialise junction between a motoneuron and a muscle fibre

Question 34

What is the motor unit

Answer 34

A single mention your own together with all the muscle fibres that it innervates

Question 35

What is a ligament

Answer 35

Connects bone to bone

Question 36

What is the tendon

Answer 36

Muscle to bone

Question 37

Knee-jerk reflex

Answer 37

When you sweat the patella ligament you got the knee jerk reflex but you’re actually hitting the quadriceps of thigh

Question 38

What is a reflex action

Answer 38

An involuntary coordinated pattern of muscle contraction and relaxation elicited by peripheral stimuli

Question 39

Process of the knee jerk reflex

Answer 39

Stretching stimulate sensory receptor (muscle spindle) Sensory neuron is activated Within integrating centre of the spinal-cord sensory neuron activates the motoneuron The motorneuron is activated Effector which is the same muscle contracts and believes the structuring The motor neurone to antagonistic muscle is inhibited

Question 40

What are the exceptions to the rule of adrenaline being release at post ganglionic neurones

Answer 40

Sweat glands and blood vessels which have sympathetic innervation where ACh is the neurotransmitter released

Question 41

Parasympathetic outflow

Answer 41

Craniosacral ( brainstem cranial nerves 3,7,9,10 and S2-S4 spinal segments)

Question 42

Sympathetic outflow

Answer 42

Thoracolumbar outflow T1-L2

Question 43

Visceral sensory

Answer 43

Relays sensory information from the core Pain , fullness,blood pressure T1-L2, S2-S4 and cranial nerves 9 and 10

Question 44

Visceral motor

Answer 44

Outflow to core and body wall Controls pupils, sweat glands, salivary glands and heart muscle and airways Thoracolumbar ( T1-L2 ) and craniosacral outflow

Question 45

Look at anatomy of sympathetic outflow to periphery

Answer 45

Look at anatomy of sympathetic outflow to periphery

Question 46

White ramps communicants

Answer 46

Called white as the pre ganglionic neurone has a myelin sheath

Question 47

Grey ramus communicants

Answer 47

Post ganglionic neurone is non myelinated and so when it goes out of the sympathetic chains , it goes via greys ramus communicans

Question 48

Sympathetic outflow to heart

Answer 48

Comes out of T1-T4 and the collection of nerves that surround the heart is known as the cardiac plexus

Question 49

Anatomy of sympathetic outflow to the viscera

Answer 49

Thoraccic nerves go into sympathetic chains but no synapse occurs in sympathetic chain. Pre ganglionic nerves travel straight down to the gut in things called sphlancic nerves where they collect and form greater, lesser and least sphlancic nerves. When they get to organs, they synapse in pre aortic Ganglia where you find cell bodies of post ganglionic neurones ( eg. In gut)

Question 50

Anatomy of parasympathetic outflow to viscera

Answer 50

Have specialised ganglia where pre and post ganglionic nerves synapse, usually in CNS