Nakamura human Anatomy Ch 14

Question 1

Functional components of the PNS

Answer 1

–Sensory inputs and motor outputs
•Categorized as somatic or visceral
–Sensory inputs also classified as general or special (taste, smell)
-Sensory receptors
-Motor endings
-Nerves and ganglia

Question 2

Autonomic nervous system

Answer 2

–General visceral motor part of the PNS
–ANS has two divisions
•Parasympathetic
•Sympathetic

Question 3

Functional Organization of the PNS

Answer 3

Sensory
   -somatic
    -visceral
Motor
    -somatic
    -visceral
           -sympathetic
           -parasympathetic
    -brachial

Question 4

Nerves and ganglia

Answer 4

Nerves – bundles of peripheral axons

Ganglia – clusters of peripheral neuronal cell bodies

Question 5

Sensory receptors

Answer 5

pick up stimuli from inside or outside the body

Question 6

Motor endings

Answer 6

– axon terminals of motor neurons

–Innervate effectors (muscle fibers and glands)

Question 7

Peripheral sensory receptors

Answer 7

Structures that pick up sensory stimuli
–Initiate signals in sensory axons
•Two main categories of sensory receptors
–Dendritic endings of sensory neurons
•Monitor general sensory information
–Complete receptor cells: specialized epithelial cells or small neurons
•Monitor most types of special sensory information

Question 8

Innervation of skeletal muscle

Answer 8

Motor axons innervate skeletal muscles
–Neuromuscular junctions (motor end plates)
•Similar to synapses between neurons
•Acetylcholine (serve as neurotransmitter btwn nerves and muscles) diffuses across the synaptic cleft
–Binds with molecules on the sarcolemma (muscle membrane)
•Motor axons branch to innervate muscle fibers

Question 9

Motor unit

Answer 9

• A motor neuron and all the muscle fibers it innervates
• motor unit 2 of diagram: 1 axon and 3 muscle fibers
• # of muscle fibers depends on # of branches the neuron has

Question 10

Cranial nerves

Answer 10

Attach to the brain and pass through foramina of the skull
•Numbered from I–XII
•Cranial nerves I and II attach to the forebrain
–All others attach to the brain stem
•Primarily serve head and neck structures
–The vagus nerve (X) extends into the abdomen

Question 11

Peripheral nervous system

Answer 11

-Nervous structures outside the brain and spinal cord

•Nerves allow the CNS to receive information and take action

Question 12

Olfactory nerves

Answer 12

• I

- sensory nerves of smell

Question 13

Optic Nerve

Answer 13

• II

- sensory nerve of vision

Question 14

Oculomotor nerve

Answer 14

• III

Innervates four of the extrinsic eye muscles

Question 15

Extrinsic eye muscles

Answer 15

• controlled by III IV and VI
• extrinsic: outside the structure/ organ
• controls eyeball movement
• muscles within the orbit but outside of the eyeball
• including the four rectus muscles (superior, inferior, medial and lateral); two oblique muscles (superior and inferior) and the levator of the superior eyelid

Question 16

Intrinsic eye muscles

Answer 16

• controls pupil

- ciliary muscle

Question 17

Trochlear nerve

Answer 17

Innervates an extrinsic eye muscle (superior oblique muscle)

IV

Question 18

Trigeminal nerve

Answer 18

V

Question 19

Abducens nerve

Answer 19

-abducts the eyeball

VI

Question 20

Facial nerve

Answer 20

Innervates muscles of facial expression

VII

Question 21

Bell’s palsy

Answer 21

Inflammatory response of nerve is to swell up and paralyzes face

Question 22

Vestibulocochlear nerve

Answer 22

Sensory nerve of hearing and balance

VIII

Question 23

Glossopharyngeal nerve

Answer 23

Innervates structures of the tongue and pharynx

IX

Question 24

Vagus nerve

Answer 24

A mixed sensory and motor nerve
Wanders into thorax and abdomen
X

Question 25

Accessory nerve

Answer 25

An accessory part of the vagus nerve | XI

Question 26

Hypoglossal nerve

Answer 26

Below tongue Runs inferior to the tongue Innervates the tongue muscles XII

Question 27

Spinal nerves

Answer 27

31 pairs – contain thousands of nerve fibers •Connect to the spinal cord •Named for point of issue from spinal cord

Question 28

Names of spinal cords

Answer 28

``` 8 pairs of cervical nerves (C1-C8) –12 pairs of thoracic nerves (T1-T12) –5 pairs of lumbar nerves (L1-L5) –5 pairs of sacral nerves (S1-S5) –1 pair of coccygeal nerves (C0) ```

Question 29

Spinal nerve order

Answer 29

-connect to the spinal cord by the dorsal root and ventral root Root then ramus (branch) then plexus

Question 30

Dorsal root

Answer 30

Contains sensory fibers | Cell bodies: located in the dorsal root ganglion

Question 31

Ventral root

Answer 31

Contains motor fibers arising from anterior gray column

Question 32

Plexus

Answer 32

A network or interjoining of nerves and blood vessels or of lymphatic vessels Brachial, lumbar, and sacral

Question 33

Dermatome

Answer 33

Area of the skin supplied by cutaneous branches from a single spinal nerve (indicates spinal nerve)

Question 34

Somatic sensory

Answer 34

Touch, pain, pressure, vibration, temperature, and proprioception in skin, body wall, and limbs Special: hearing, equilibrium, smell, vision

Question 35

Visceral sensory

Answer 35

Stretch, pain, temperature, chemical changes, Ian's irritation in viscera; hunger and nausea Special: taste

Question 36

Somatic motor

Answer 36

Motor innervation of all skeletal muscles (except pharyngeal arch muscles)

Question 37

Brachial motor

Answer 37

Innervation of pharyngeal arch muscles

Question 38

Visceral motor

Answer 38

Motor innervation of smooth muscle, cardiac muscle, and glands (equivalent to the autonomic nervous system)