Bio 203 Lecture 14

Front 1

senses that involve receptors in the skin, muscles, tendons, joints, and visceral organs

Back 1

somatic senses

Front 2

hearing, balance, vision, taste, and smell are what kind of sense?

(don't think too hard)

Back 2

special senses

Front 3

3 types of sensory receptors

Back 3

specialized nerve cells (ex. photoreceptors in eye)
nerve endings
non-neuronal receptor cells (some epithelial cells)

Front 4

process of converting part of the energy of a stimulus into a meaningful electrical signal

Back 4

transduction

Front 5

5 types of sensory receptors based on what they respond to

Back 5

-chemoreceptors
-nociceptors (respond to pain)
-thermoreceptors
-mechanoreceptors
-photoreceptors

Front 6

t/f, sensory receptors detect a specific, unique stimulus.

Back 6

true

Front 7

t/f, the stimulus produces an electrical change in the receptor, usu. by opening sodium channels.

Back 7

true

Front 8

small depolarization of the sensory receptor membrane when stimulated below the threshold

Back 8

generator potential

Front 9

the frequency of action potentials passing along an afferent nerve fiber

Back 9

frequency code

Front 10

some cases (e.g. pressure) where intensity is signalled by # of receptors responding

Back 10

population code

Front 11

see diagram on page 274.

Back 11

do it.

Front 12

sensations are coded by the type of receptor stimulated- this is called?

Back 12

labelled line code

Front 13

t/f, how a receptor is stimulated affects the sensation perceived.

Back 13

FALSE!

Front 14

the frequency of action potentials generated by receptors decreases during continuous stimulation

Back 14

sensory adaptation

Front 15

t/f, receptors adapt at different rates.

Back 15

true

ex- pacinian corpuscles adapt faster than muscle stretch receptors

Front 16

a large-diameter, myelinated fiber that conducts impulses 50m/sec

Back 16

A-d fiber

Front 17

small-diameter, unmyelinated fiber that conducts impulses 5m/sec

Back 17

C fiber

Front 18

type of senses mediated by receptors in the skin that give rise to sensations such as touch, pressure, tickle, temperature, & pain

Back 18

exteroceptive senses

Front 19

senses mediated by receptors in the muscles, tendons, & joints; measure physical properties such as muscle length, tendon tension

Back 19

proprioceptive senses

Front 20

mediated by receptors in the viscera and the brain

Back 20

visceroceptive/interoceptive senses

Front 21

exteroceptors that belong to the class of mechanoreceptors; respond to deformation of the skin

Back 21

tactile receptors

Front 22

elongated, encapsulated endings in the dermal papillae of hairless skin; in the lips, fingertips, palms, soles, genitalia, & nipples; responsible for fine tactile discrimination

Back 22

Meissner's corpuscles

Front 23

sensitive, rapidly-adapting receptor in the subcutaneous layers of the hands, feet, genitals, and breasts; respond best to vibration

Back 23

Pacinian corpuscles

Front 24

receptors with spiral endings of nerve fibers wrapped around hair follicles; rapidly-adapting

Back 24

hair receptors

Front 25

slow-adapting touch receptors in skin

Back 25

Merkel endings (discs) and Ruffini endings

Front 26

thermal sensation receptors- free nerve endings

Back 26

warm receptors (25-45 degrees C)
cold receptors (10-30 degrees C)

Front 27

stimuli for pain receptors include... (3 things)

Back 27

mechanical, thermal, and chemical agents

Front 28

when tissue is damaged, two powerful peptides may be released. what are they?

Back 28

bradykinin & substance P

Front 29

what do prostaglandins do?

Back 29

enhance pain

Front 30

how does aspirin work?

Back 30

by inhibiting the biosynthesis of prostaglandins

Front 31

short-lived, well-localized pain associated only with the skin & carried by A-d afferents

Back 31

fast pain

Front 32

poorly localized pain conveyed by C afferents & associated with the skin, joints, internal organs, and muscles (all areas with nociceptors)

Back 32

slow pain

Front 33

what affects the perception of pain?

Back 33

mental attitude, emotional state, drugs, other stimuli

Front 34

what region of the brain, when stimulated, causes analgesia w/o loss of tactile sensitivity?

Back 34

periaqueductal region

Front 35

what is analgesia?

Back 35

deadening of pain sensitivity

Front 36

name 4 important substances in the brain's endogenous analgesic system.

Back 36

-endogenous opioid peptides (enkephalins, endorphins, dynorphin)
-GABA
-serotonin
-Substance P

Front 37

what do endogenous opioids (enkephalins, endorphins, dynorphin) cause?

Back 37

analgesia & euphoria

Front 38

how does the brain's endogenous analgesic system operate?

Back 38

-activation of neurons in the periaqueductal gray excites neurons that use serotonin
-neurons stimulate inhibitory interneurons in spinal cord
-interneurons release enkephalin, which inhibits neurons that transmit pain impulses to the brain

Front 39

see diagram on 281.

Back 39

learn it, know it.

Front 40

when pain is felt cutaneously as a result of nociceptive stimulus to an internal organ

Back 40

referred pain, causes by shared nerve pathways

Front 41

proprioceptors that provide info. on muscle length

Back 41

muscle spindles

Front 42

specialized muscle fibers in a muscle spindle; have specialized nerve endings & a central fluid-filled sheath

Back 42

intrafusal fibers

Front 43

proprioceptors that provide info. about the tension exerted by a muscle on a tendon

Back 43

Golgi tendon organs

Front 44

where are golgi tendon organs found?

Back 44

between collagen fiber bundles close to where the tendon and muscle connect

Front 45

possible function of Golgi tendon organs

Back 45

protective- can inhibit muscular contraction if it's so strong that it damages the tendon

Front 46

see diagram on 284.

Back 46

no, really, you need to know it.

Front 47

proprioceptors in the joints that transmit info. about joint movement & position

Back 47

joint kinesthetic receptors