A&P exam 13

lumbar plexus

arises from L1-L2

patellar reflex

example of stretch reflex

contracting

the muscle activates the golgi tendon organs

receptor level

the sensor receptors

cords

lateral, medial, and posterior fiber bundles

sciatic

the major nerve of the sacral plexus

encapsulated simple receptors

-meissner's corpuscles -pacinian corpuscles -muscle spindles, Golgi tendon organs, and Ruffini's corpuscles

segmental, projection, precommand

3 levels of motor control

Trigeminal nerve Both (general sensations)

Cranial nerve V sensory or motor function?

amitotic

Damage to nerve tissue is serious because mature neurons are

dorsal root; skin; spinal cord

First-order neurons: soma reside in ________________ and conduct impulses from the __________ to the _____________

adapt quickly

Receptors responding to pressure, touch, and smell

Thalamus; cortex

Third-order neurons: located in the _____________ and conduct impulses to the _____________ of the cerebrum

roots-trunks-divisions-cords

What are the four major branches of the brachial plexus in order?

ventral; efferent

____________ roots arise from the anterior horn and contain motor _____________ fibers

31; head

_____________________ pairs of mixed nerves arise from the spinal cord and supply all parts of the body except the __________

pattern recognition

ability to recognize patterns in stimuli (e.g., melody, familiar face)

Babinski's sign

abnormal plantar reflex indicating corticospinal damage where the great toe dorsiflexes and the smaller toes fan laterally

stretching the muscles

activates the muscle spindle

PNS

all neural structures outside the brain and spinal cord

divisions

anterior and posterior serve the front and back of the limb

nerve plexuses

are found in the cervical, brachial, lumbar, and sacral regions

receptors

are structurally classified as either simple or complex encapsulated and unencapsulated varieties

sacral plexus

arises from L4-S4

antagonist

as a result, the contracting muscle relaxes and the _________________ contracts

circuit level

ascending pathways

median of brachial plexus

branches to most of the flexor muscles of arm

chains of three neurons

conduct sensory impulses upward to the brain

projection level

consists of brain stem motor areas and helps control reflex and fixed-pattern activity

segmental level

consists of the spinal cord and circuits control locomotion and specific, oft-repeated motor activity

olfactory nerve sensory-smell

cranial nerve I sensory or motor function?

Optic nerve sensory-vision

cranial nerve II sensory or motor function?

oculomotor nerve motor

cranial nerve III sensory or motor function?

Trochlear nerve motor

cranial nerve IV sensory or motor function?

glossopharyngeal nerve both (sensory-taste)

cranial nerve IX sensory or motor function?

Abducens nerve motor

cranial nerve VI sensory or motor function?

Facial nerve both (sensory-taste)

cranial nerve VII sensory or motor function?

vestibulocochlear nerve both (sensory-hearing and balance)

cranial nerve VIII sensory or motor function?

Vagus nerve both (sensory-taste)

cranial nerve X sensory or motor function?

Accessory nerve motor

cranial nerve XI sensory or motor function?

Hypoglossal nerve motor

cranial nerve XI sensory or motor function?

pain receptors and proprioception

do not exhibit adaptation

roots

five ventral rami (c5-T1)

golgi tendon organs

for skeletal muscles to perform normally: ________________ (proprioceptors) must constantly inform the brain as to the state of the muscle

muscle spindles

for skeletal muscles to perform normally: stretch reflexes initiated by ____________________ must maintain healthy muscle tone

schwann cells

form regeneration tube and secrete growth factors

unencapsulated simple receptors

free dendrite nerve endings -merkel (tactile) discs -hair follicle receptors

8

how many cervical nerves are there?

1

how many coccygeal nerves are there?

5

how many lumbar nerves are there?

5

how many sacral nerves are there?

12

how many thoracic nerves are there?

repaired

if the soma of a damaged nerve remains intact, damage can be ______________

acetylcholine

in innervation of skeletal muscle, ____________ is the neurotransmitter that diffuses across the synaptic cleft

acetylcholine; norepinephrine

in innervation of visceral muscle and glands, _______________ and _____________ are used as neurotransmitters

slower

in innervation of visceral muscle and glands, visceral responses are ___________ than somatic responses

regulate motor activity precisely start or stop movements coordinate movements with posture block unwanted movements monitor muscle tone

in the precommand level, cerebellar and basal nuclei systems:

input

in the somatosensory system, ______________ comes from exteroceptors, proprioceptors, and interoceptors

intrinsic

inborn reflexes

superficial reflexes

initiated by gentle cutaneous stimulation

radial of brachial plexus

innervates essentially all extensor muscles

axillary nerve of brachial plexus

innervates the deltoid and teres minor

reflexes

involve only peripheral nerves and the spinal cord

reflex

is a rapid, predictable motor response to a stimulus

flexor reflex

is initiated by a painful stimulus (actual or perceived) that causes automatic withdrawal of the threatened body part

plantar reflex

is initiated by stimulating the lateral aspect of the sole of the foot

dermatome

is the area of skin innervated by the cutaneous branches of a single spinal nerve

sensation

is the awareness of changes in the internal and external environment

perception

is the conscious interpretation of those stimuli

phrenic nerve

is the major motor and sensory nerve of the diaphragm

acquired

learned reflexes

perceptual level

neuronal circuits in the cerebral cortex

adaptation

occurs when sensory receptors are subjected to an unchanging stimulus

golgi tendon reflex

opposite of the stretch reflex

PNS

provides links to and from the external environment

merkel's discs, Ruffini's corpuscles

receptors responding slowly include

contracting the muscles

reduces tension on the muscle spindle

axons

regenerate damaged part

macrophages

remove debris

chemoreceptors

respond to chemicals (examples: smell, taste, changes in blood chemistry)

proprioceptors

respond to degree of stretch found in skeletal muscles, tendons, joints, ligaments, and connective tissue coverings of bones and muscles

Photoreceptors

respond to light energy (example: retina)

exteroceptors

respond to stimuli arising outside the body sensitive to touch, pressure, pain and temperature

interoceptors

respond to stimuli arising within the body sensitive to chemical changes, stretch, and temperature changes

Mechanoreceptors

respond to touch, pressure, vibration, stretch, and itch

dorsal; afferent

roots arise from sensory neurons in the ganglion and contain sensory ______________ fibers

dorsal horn; thalamus

second-order neurons: soma reside in the ________________ of the spinal cord and transmit impulses to the ____________

musculocutaneous nerve of brachial plexus

sends fibers to the biceps brachii and brachialis

Thermoreceptors

sensitive to changes in temperature

Nociceptors

sensitive to pain-causing stimuli

ulnar of brachial plexus

supplies the flexor carpi ulnaris and part of the flexor digitorum profundus

innervation of skeletal muscle

takes place at a neuromuscular junction

quadriceps

tapping the patellar tendon stretches the ___________ and starts the reflex action

Quality discrimination

the ability to identify submodalities of a sensation (e.g., sweet or sour tastes)

the simulated side is withdrawn the contralateral side is extended

the cross extensor reflex has two parts:

sciatic nerve

the longest and thickest nerve of the body

femoral; obturator

the major nerves of the lumbar plexus are the ___________ and the ______________

phrenic nerve

the most important nerve of the cervical plexus

cranial nerve X: Vagus

the only cranial nerve that extends beyond the head and neck

antagonistic

the quadriceps contract and the _____________ hamstrings relax

downward flexion of the toes

the response to plantar reflex is

lowest

the segmental level is the ___________ level of motor hierarchy

receptor level, circuit level, perceptual level

the three main levels of neural integration in the somatosensory system are:

trunks

upper, middle, and lower, which form divisions

feature abstraction

used to identify a substance that has specific texture or shape

C5-T1

what is the brachial plexus formed by?

C1-C4

what is the cervical plexus formed by?

stimulus

when processing at the receptor level, _____________ energy must be converted into a graded potential

receptor

when processing at the receptor level, the ______________ must have specificity for the stimulus energy