Peripheral NS

Question 1

2 main categories of sensory receptors

Answer 1

1. Free nerve endings of sensory neurons (monitor general sensory information)
2. Complete receptor cells (specialized epithelial cells or small neurons that monitor most types of special sensory information)

Question 2

Exteroreceptors

Answer 2

Sensitive to stimuli arising from outside the body
At or near body surfaces
Include receptors for touch, pressure, pain and temperature

Question 3

Interoreceptors

Answer 3

Receive stimuli from internal viscera
Located in digestive tube, bladder, and lungs
Monitor a variety of stimuli (changes in chemical composition, taste stimuli, stretching of tissues, temperature)

Question 4

Proprioceptors

Answer 4

Body position or movement
Located in skeletal muscles, tendons, joints, and ligaments
Monitor degree of stretch
Send inputs on body movement to the CNS

Question 5

Muscle spindles
(and 2 types)

Answer 5

Type of proprioceptor
Measure the changing length of a muscle
Are embedded in the perimysium between muscle fasicles
Intrafusal muscle fibers: modified skeletal muscle fibers located within muscle spindles
Anulospiral endings: located around middle of intrafusal fibers, stimulated by rate and degree of stretch

Question 6

Tendon organs

Answer 6

Type of proprioceptor
Are located near the muscle-tendon junction
Monitor tension within tendons

Question 7

Joint kinesthetic receptors

Answer 7

Type of proprioceptor
Sensory nerve endings within the joint capsules
4 types: Pacinian corpuscles, Ruffini endings, free nerve endings, receptors resembling tendon organs

Question 8

How many cranial nerves are there?

Answer 8

12

Question 9

How many spinal nerves are there

Answer 9

31 pairs that connect to the spinal cord
8 C
12 T
5 L
5 S
1 Co

Question 10

Nerve plexus and where are they found

Answer 10

Web/network of nerves
Primarily serve the limbs
Fibers from the ventral rami criss cross
Happens in C, L, and S

Question 11

Dermatomes

Answer 11

An area of skin innervated by cutaneous branches of a single spinal nerve

Question 12

3 pathways of sympathetic innervation

Answer 12

1. Synapse in trunk ganglion at the same level
2. Synpase in trunk ganglion at higher or lower level
3. Pass through sympathetic trunk to synapse in a collateral ganglion anterior vertebral column

Question 13

3 ways collateral ganglia differ from sympathetic trunk ganglia

Answer 13

1. Unpaired, not segmentally arranged
2. Occur only in abdomen and pelvis
3. Lie anterior to vertebral column

Question 14

4 main collateral ganglia

Answer 14

Celiac
Superior mesenteric
Inferior mesenteric
Inferior hypogastric ganglia

Question 15

Visceral pain

Answer 15

No pain results when visceral organs are cut
Results from chemical irritation or inflammation
Often presents as referred pain

Question 16

Which regions of the hypothalamus control parasymp vs symp functions?

Answer 16

Symp: lateral and posterior
Parasymp: medial and anterior