PNS & ANS (W3)

Question 1

What its the PNS

Answer 1

outside the CNS
- receives information and gives info to CNS

Question 2

What are the
- dorsal
- ventral root

Answer 2

Dorsal - sensory input
Ventral - motor output

Question 3

What is the purpose of the ganglion

Answer 3

bundle of cell bodies transmitting sensory information

Question 4

What is the weakest point in you spine

Answer 4

intervertebral foramina

Question 5

What is the ventral horn

Answer 5

where motor nuerons have their cell bodies
- towards bottom of grey matter

Question 6

How many spinal nerves do we have

Answer 6

31 pairs

Question 7

Name the spinal nerves

Answer 7

• 8 cervial
  -12 thoracic
• 5 lumbar
• 5 sacral
• 1cocygeal

Question 8

What are the peripheral nerve and where do they arise form

Answer 8

mix of motor and sensory neurons and arise from spinal nerves

Question 9

Where do the peripheral nerve originate

Answer 9

brian and spinal cord

Question 10

What is the ventral rami
(nerve plexus)

Answer 10

supply the limbs via the interwoven network of fibres

Question 11

What is a communicating ramus

Answer 11

further branches of spinal nerves
- connect sympathetic chain
- occur at spinal level T1-L3

Question 12

What is a dermatome

Answer 12

area of skin innervated by sensory axons of a single dorsal nerve root

Question 13

What are nerve coverings

Answer 13

continuum of the the meninges

Question 14

Describe the layers of the nerve coverings

Answer 14

Epineurium - continuum of there dura mater & provides mechanical strength for the nerve
Perineurium -
Endonerurium - continuum of the arachnid matter

Question 15

What are Schwann cells (oligodendrocytes)

Answer 15

• supportive glial cells in nerves
• regulate the axons keeping the environment the same

Question 16

What determines how quickly the information travels

Answer 16

• width (wider = faster, more myelin)

Question 17

What is signal transduction in a sensory component

Answer 17

process of converting the energy of a stimulus into an electrical signal

Question 18

What ending is responsible for signal transduction

Answer 18

somatosensory by opening of cation channel producing a depolarising receptors potential

Question 19

What is a receptive field

Answer 19

area of skin inverted by a single sensory afferent

Question 20

What is 2 point discrimination

Answer 20

measures the minimum inter-stimulus distance required to perceive 2 stimuli and different point

Question 21

What is visceral sensory information

Question 22

What does the dorsal root ganglia do in visceral sensory information

Answer 22

tends visceral afferent through sympathetic nerves

Question 23

What are proprioceptors

Answer 23

muscle, tendons and joint mechanoreceptors