Bio223 Csn Exam 5 Ch 15

Front 1

sensory receptors

Back 1

specialized cells or cell processes that provide your central nervous system with info about internal/external conditions outside of the body

Front 2

_____ , ______ , & _______ make up the afferent division of the nervous system

Back 2

1. receptors
2. sensory neurons
3. sensory pathways

Front 3

general senses

Back 3

describes our sensitivity to temp., pain, touch, pressure, vibration, & proprioception

Front 4

When pressure sensations arrive, the _______ the pressure, the higher the frequency of action potentials

Back 4

harder

Front 5

transduction

Back 5

a sensory receptor detects an arriving stimulus & translates it into an action potential that can be conducted to CNS

Front 6

receptor specificity

Back 6

may result from the structure of a receptor cell, or the presence of accessory cells/structures tthat sheild the receptor from other stimuli

Front 7

branching tips of dendrites that exted through a tissue; not protected by accessories; little receptor specificity

Back 7

free nerve endings

Front 8

receptive field

Back 8

the area monitored by a single receptor cell

Front 9

the _____ the receptor field, the better the ability to locaalize stimulus

Back 9

smaller

Front 10

transduction

Back 10

_______ begins when a stimulus changes the transmembrane potential of a receptor cell

Front 11

________ is graded depolarization or hyperpolarization as a result of transduction. The _______ the stimulus, the larger the _______.

Back 11

1. receptor potential
2. larger
3. receptor potential

Front 12

generator potential

Back 12

a depolorizing receptor potential in a neural receptor

Front 13

labeled line

Back 13

the link between a peripheral receptor & cortical neuron consisting of axons carrying info about one modality or type of stimulus

Front 14

sensory coding

Back 14

the translation of complex sensory info into meaningful patterns of action potentials

Front 15

tonic receptors

Back 15

sensory neurons that are always active; indicates background level of stimulation

Front 16

phasic receptors

Back 16

sensory neurons that become active to provide info about the intensity & rate of change of a stimulus

Front 17

adaptation

Back 17

a reduction in sensitivity in the presense of constant stimulus

Front 18

peripheral adaptation

Back 18

occurs when the level of receptor activity changes by responding stongly at first, then gradually declines

Front 19

involves the inhibition of nuclei along a sensory pathway; restricts info sent to cerebral cortex

Back 19

central adaptation

Front 20

nociceptors

Back 20

pain receptors located in superficial portios of skin, periostea of bones, & walls of blood vessels

Front 21

nociceptors may be sensitive to:
1.
2.
3.

Back 21

1.mechanical damage
2. dissolved chemicals
3. extremes of temperature

Front 22

Myelinated type ___ fibers carry ______ pain, or prickling, pain, such as from a deep cut.

Back 22

1. A
2. Fast

Front 23

Slower, type ___ fibers carry ____ pain, that is burning or aching

Back 23

1. C
2. Slow

Front 24

The sensory neurons that bring pain sensations into the CNS release _____ and/or _______ as neurotransmitters.

Back 24

1. glutamate
2. substance P

Front 25

thermoreceptors

Back 25

free nerve endings located in the dermis, skeletol muscles, liver and hypothalamus; temperature receptors

Front 26

which receptor is more numerous, cold or warm?

Back 26

cold

Front 27

mechanoreceptors

Back 27

sensitive to stimuli that distort their mechanically gated ion channels, their gates open or close in response to stretching, compression,twisting, or other distortions of their plasma membranes

Front 28

three classic mehanoreceptors:
1.
2.
3.

Back 28

1. tacticle receptors
2. baroreceptors
3. proprioceptors

Front 29

tactile receptors

Back 29

provide closely related sensations of touch, pressure, & vibration

Front 30

baroreceptors

Back 30

detect pressure change in walls of blood vessels, portions of digestive, respiratory, & urinary tracts

Front 31

proprioceptors

Back 31

monitor positions of joints & skeletol muscles

Front 32

tonic receptors with small receptive fields that provide touch sensations between epidermal cells

Back 32

free nerve endings

Front 33

tactile receptors wherever hairs are located; nerve endings that monitor distortions and movements across body surface

Back 33

root hair plexus

Front 34

tactile receptors w/very small receptive fields that are very sensitive & make close contact w/large areas of epithelial cells in stratum basale of skin

Back 34

Merkel Discs

Front 35

tactile receptors that percieve sensations of fine touch & pressure in LOW frequency vibration & are most abundant in eyelids, lips, fingertips, nipples, & external genitalia

Back 35

Meissner's Corpuscles

Front 36

Lamellated Corpuscles

Back 36

tactile receptor sensitive to deep pressure; located in superficial or deep fascia, mammary glands, & fingers as somatic sensory info, or mesentaries, pancreas, & urinary walls as visceral sensory info

Front 37

Ruffini Corpuscles

Back 37

tactile receptor sensitive to pressure & distortion of the skin, located in deep dermis, & show little adaptation

Front 38

Muscle spindle

Back 38

a proprioreceptor that monitors skeletal/muscle length & triggers stretch reflexes

Front 39

golgi tendon organs

Back 39

a proprioreceptor stimulated by tension in the tendon, & monitors the external tension developed during muscle contraction

Front 40

receptors in joint capsules

Back 40

a proprioceptor richly innervated by nerve endings that detect pressure, tension, & movement at the joint

Front 41

most proprioceptive info is processed at ______ levels

Back 41

subconscious

Front 42

specialized chemoreceptive neurons that can detect small changes in the concentration of specific chemical compounds, reponding only to water/lipid-soluble substances dissolved in body fluids

Back 42

chemoreceptors

Front 43

first-order-neuron

Back 43

a sensory neuron that delivers sensations to CNS, located in dorsal root ganglion or nerve ganglion

Front 44

second-order neuron

Back 44

an interneuron located in the spinal cord or brain stem

Front 45

If a sensation is to reach our awareness, the axos of the ______ neurons ascend w/out crossig over & synapse on neurons of the primary sensory cortex of the cerebral hemisphere.

Back 45

third-order

Front 46

somatic sensory pathways

Back 46

carry sensory info from skin & musculature of the body wall, head, neck, & limbs

Front 47

three somatic sensory pathways:
1.
2.
3.

Back 47

1. spinothalamic pathway
2. posterior column pathway
3. spinocerebellar pathway

Front 48

Spinothalamic pathway

Back 48

carries sensations of poorly localized touch, pain, pressure, & temp. ascending

Front 49

anterior spinothalamic tracts

Back 49

carry crude touch & pressure sensations from the right side of the body

Front 50

lateral spinothalamic tracts

Back 50

carry pain & temp sensations from right side of body

Front 51

posterior column pathway

Back 51

carries sensatins of highly localized fine touch, pressure vibration, & proprioception; contains fasciculus gracilis (inferior) & fasiculus cuneatus (superior); axons cross over

Front 52

spinocerebellar pathway

Back 52

where the cerebellum receives proprioceptive info about positios of skeletal muscles, tendons, & joints;
asceding

Front 53

posterior spinocerebellar tracts

Back 53

proprioception

Front 54

anterior spinocerebellular tracts

Back 54

proprioception

Front 55

referred pain

Back 55

ex: pain of heart attack felt in arm

Front 56

crossing of axon from opposite sides of brain

Back 56

decussation

Front 57

sensory homunculis

Back 57

map of the primary sensory cortex w/distorted body features

Front 58

Which 3 descending tracts make up the corticospinal pathway?

Back 58

1. corticobulbar tracts
2. lateral corticospinal tracts
3. anterior corticospinal tracts

Front 59

vestibulospinal tracts

Back 59

carry info related to balance & posture

Front 60

medial pathway

Back 60

primarily controls gross movements of neck, trunk, & proximal limbs

Front 61

rubrospinal tracts

Back 61

cotrol muscle tone & movements of the distal muscles of upper limbs

Front 62

basal nuclei

Back 62

adjust the motor commands issued in other processing centers & provide background patterns of movement involved in voluntary motor activities

Front 63

cerebellum

Back 63

monitors proprioceptive sensations, visual info, & vestibular sensations; essential for precise control of movements

Front 64

voluntary responses

Back 64

more complex & require more time to execute

Front 65

spinal & cranial reflexes

Back 65

provide rapid, involuntary , preprogrammed responses to preserve homeostasis

Front 66

3 steps for transduction to occur:

Back 66

1. arriving stimulus alters trsmembrane potential of receptor membrane
2. the receptor potential directly or indirectly affects sensory neuron
3. action potentials travel to CNS along afferent fiber

Front 67

motor homunculus

Back 67

a mapped out are, of the primary motor cortex, provides indication of motor control available

Front 68

sensory homunculus

Back 68

indicates degree of sensitivity of peripheral sensory receptors

Front 69

what are the three motor tracts make up the medial pathway?

Back 69

1. vestibulospinal tract
2. tectospinal tract
3. reticulospinal tract