Human Physiology Chapter 10

Front 1

Characteristics of Sensory Receptors

Back 1

.

Front 2

what is a sensory receptor?

Back 2

Specialized nerve cell that is designed to respond to a specific sensory stimulus

Front 3

Give examples of sensory stimulus

Back 3

touch, pressure, pain, light, sound, position in space and vibration 

Front 4

what are 3 types of sensory receptors?

Back 4

1.exteroceptors

2.interoceptors

3. proprioceptors

Front 5

What are the functional categories according to the type of signal they transduce

Back 5

-chemoreceptors: sense chemicals in the environment (taste, smell) or blood

-photoreceptors: sense light

-thermoreceptors: respond to cold or heat

-mechanoreceptors: stimulated by mechanical deformation of the receptor (touch, hearing)

Front 6

cutaneous receptors

Back 6

respond to pain, temperature, pressure, vibration, and discrimative touch 

Front 7

Nociceptors

Back 7

pain receptors that depolarize when tissues are damaged

 

Front 8

what type of stimuli does nociceptors include

Back 8

-heat, cold, pressure, or chemicals

 

Front 9

what are they main neurotransmitters foe Nocicpetors? 

Back 9

-glutamate and substance P are the main neurotransmitters

Front 10

How can the preception of pain be enhanced?

Back 10

by emotiond, concepts, and expectations

Front 11

what are prorioceptors?

Back 11

found in muscles, tendons, and joints. provide a sense of body position and allows fine muscle control

Front 12

What are the 5 special sense receptors?

Back 12

1. visual

2. olfactory

3. auditory

4. gustatory

5. equilibrium

Front 13

Receptors cannot be classified by the origin of the information  

 

TRUE or FALSE 

Back 13

FALSE, receptors can be classified by the origin of the information (exteroceptors, interoceptors)

 

Front 14

What are exteroceptors? give examples

Back 14

respond to stimuli from outside the body; includes cutaneous receptors and special senses.

-examples: visual, auditory, tactile, gustatory, and olfactory

 

Front 15

What are interoceptors:

Back 15

respond to internal stimuli; found in organs; monitor blood pressure, pH, and oxygen concentrations

Front 16

Receptors can not be categorized based on how they respond to stimulus

 

TRUE or FALSE

Back 16

FALSE, receptores can be categorized on how they respond to stimulus

Front 17

Define Phasic Receptor

Back 17

responds with a a burst of activity when stimulus is first applied but quickly adapt to the stimulus be decreasing response

Front 18

what kind of changes can Phasic Receptors alert us to?

Back 18

environmental changes

Front 19

does phasic receptors allow sensory adaptaion?

Back 19

yes phasic receptors do allow for sensory reception

Front 20

what is sensory adaptation

Back 20

cease to pay attention to constant stiumli

Front 21

what are some examples of phasic receptors

Back 21

smell, touch, temperature 

Front 22

what is a tonic receptors

Back 22

they maintain a high firing rate as log as the stimulus is applied

Front 23

what is an example of a tonic receptor

Back 23

pain

Front 24

is tonic receptor fast or slow adapting?

Back 24

slow adapting

Front 25

is phasic receptor fast or slow adapting?

Back 25

fast adapting

Front 26

what is paradoxical cold

Back 26

pereception of cold at different temperatures 

Front 27

What is a generator potential?

Back 27

stimuli that produces depolarization

Front 28

what do receptors behave like?

Back 28

dendrites of neurons

Front 29

what is pacinian corpuscle

Back 29

-one of the four major types of mechanoreceptors.

-They are nerve endings in the skin responsible for sensitivity to vibration and pressure.

Front 30

what is a generator (receptor) potential?

Back 30

type of graded potential, is the transmembrane potential difference of a sensory receptor

Front 31

increasing the ________increases the magnitude of the generator potential until threshold is met and an ______________ occurs

Back 31

pressure, action potential

Front 32

Generator (receptor) Potential is a graded response.

 

TRUE or FALSE

Back 32

TRUE

Front 33

what happens with the generator potential in Pacinian corpuscles which are phasic receptors, if pressure is maintained

Back 33

generator is diminished

Front 34

how does the  generator potential in tonic receptors relate to stimulus intensity?

Back 34

the generator is proportional to the intensity of the stimulus. 

Front 35

in tonic receptors how does the increased intensity effect frequency of action potentials?

Back 35

the frequency of action potentials increases with the intensity, after the threshold is reached

Front 36

define Cutaneous Receptors

Back 36

type of sensory receptor found in the dermis or epidermis. They are a part of thesomatosensory system.

-Cutaneous receptors include e.g. 

    -cutaneous mechanoreceptors,

    -nociceptors (pain)

    -thermoreceptors (temperature).

Front 37

what are naked dendrites of sensory neurons?

Back 37

pain, cold, and heat receptors

Front 38

what kind of receptors have a special structure arounf their dendrites?

Back 38

touch and pressure receptors

Front 39

give examples of touch and pressure receptors (mechano-receptors)

Back 39

1. Merkel's disks

2. Meissner's corpuscles

3. Pacinian corpuscles

4. Ruffinin corpuscles

 

Front 40

what is the structure, sensation, and location of:

 

Free nerve endings

Back 40

-unmyelinated dendrites of sensory neurons

-light touch; hot; cold;nocicpetion (pain)

-around harid follicles; throughout skin

Front 41

what is the structure, sensation, and location of:

 

Merkel's discs

Back 41

-expanded dendritic endings associated with 50-70 specialized cells

-sustained touch and indented depth

-base of epidermis (stratum basale)

 

Front 42

what is the structure, sensation, and location of:

 

Ruffini Corpuscles (endings)

Back 42

-Enlarged dendritic endings with open, elongated capsule

-skin stretch

-deep in dermis and hypodermis

 

Front 43

what is the structure, sensation, and location of:

 

Meissner's corpuscles

Back 43

-dendrites encapsulated in connective tissue

-changes in texture; slow vibrations

-upper dermis (papillary layer)

 

Front 44

what is the structure, sensation, and location of:

 

Pacinian Corpuscles

Back 44

-dendrites encapsulated by concentric lamellae of connective tissue structures

-deep pressure; fast vibrations

-deep in dermis

Front 45

Characteristic of Merkel's discs

Back 45

indentation

Front 46

Characteristic of Root hair plexus

Back 46

light brushing

Front 47

Characteristic of Pacinian Corpuscle

Back 47

vibration; deep pressure

Front 48

Characteristic of Meissner's Corpuscle

Back 48

changes in texture

Front 49

Characteristic of Free nerve ending

Back 49

touch, pain, hot, cold

Front 50

Characteristic of Ruffini endings

Back 50

Skin stretch

Front 51

define cold receptors

Back 51

stimulated by cold and inhibited by warm

Front 52

do more receptors respond to cold or hot?

Back 52

there are many more receptors that respond to cold than to hot

Front 53

where are cold receptors located?

Back 53

close to the epidermis

Front 54

what else can cold receptors respond to?

Back 54

menthol

Front 55

what is the temperature range of response for cold receptors?

Back 55

8-28 degrees Celcius

Front 56

what kind of channel can cold receptors serve as

Back 56

as an ion channel for sodium and calcium- a transient receptor potential (TRP)

Front 57

Define warm receptors

Back 57

excited by warming and inhibited by cooling

Front 58

where are warm receptors located??

Back 58

deeper in the dermis

Front 59

Warm receptors are the same as receptors that detect painful heat

 

TRUE or FALSE

Back 59

FALSE, they are different

Front 60

define hot receptor 

Back 60

receptor that experiences pain by a hot stimulus is sensed by a peical nociceptor, called a capsaicin receptor

Front 61

what kind of channel can a hot receptor serve as

Back 61

serves as an ion channel for sodium and calcium- a TRP channel

Front 62

what temperature is the hot receptor activated?

Back 62

43 degrees celcius of higher

Front 63

Nociceptors can by _______or _________

Back 63

myelinated neurons, unmyelinated neurons

Front 64

sudden sharp pain is transmitted by what type of neurons

Back 64

myelinated neurons

Front 65

dull persistant pain is transmitted by what type of neurons?

Back 65

unmyelinated neurons

Front 66

how can Nociceptors be activated?

Back 66

-chemicals released by damaged tissue (ATP)

-pH change 

-mechanical stimuli

Front 67

how is acute itch stimulated?

Back 67

by histamine release form mast cells and basophils

Front 68

define mast cells

Back 68

chemicals are very irritating and cause itching, swelling, and fluid leaking from cells

Front 69

define basophils

Back 69

type of white blood cell (leukocyte) with coarse, bluish-black granules of uniform size within the cytoplasm. 

Front 70

what kind of itch it stimulated by other chemicals and does not respond to antihistamines

Back 70

chronic itch

Front 71

what stimulates unmyelinated sensory axons to the spinal cord

Back 71

Receptors

Front 72

what  steps does the neural pathways from the Somatesthetic Sensations for pressure receptors and proprioceptors

Back 72

1. First they are carried by a large myelinated fibers that ascend the dorsal columns of the spinal cord on the ipsilateral side

 

2. Then they synapse in the medulla oblongata

 

3. The seond tier of neurons cross sides as they ascend the medial lemniscus to the thalamus, where they synapse

 

4. Third-order neurons go to the postcentral gyrus in the parietal lobe (somatosensroy cortex) 

Front 73

what steps does the neural pathways from the Somatesthetic sensations for heat, cold, and paint receptors

Back 73

1. First carried into spinal cord by thing myelinated and unmyelinated neurons to the lamina of the dorsal gray horns

 

2. Synapse within spinal cord onto second-order neuron

 

3. Cross sides and ascend lateral spinothalamic tract

 

4. Synapse on thrid-order neurons in thalamus and continue to the post central gyrus

Front 74

When does emotional response to pain occur?

Back 74

when information is sent from the thalamus to the anterior is sent from the thalamus to the anterior cingulate gyrus (part of the limbic system)

Front 75

Define referred pain

Back 75

when the brain may interpret heart pain as arm pain, or gallbladder pain as back pain

Front 76

What is the receptive field?

Back 76

the area of skin that when stimulated, changes the firing rate of a neuron

Front 77

The size of the receptive field depends on what?

Back 77

the density of receptors in that region of skin

Front 78

There are alot of receptors in the back and legs so the receptive fields are small

 

TRUE or FALSE

Back 78

FALSE, they are large because there are few receptors

Front 79

There are few receptors in the fingertips, so the receptive fields are large

 

TRUE or FALSE

Back 79

FALSE, there are many receptors in the fingertips, so the receptive fields are small

Front 80

The more receptors the _______the field, the ________the area of the somatosensory cortex

Back 80

smaller, larger

Front 81

greater tactile acuity - sharpness of the sensation=?

Back 81

a small reeptive field

Front 82

How can receptive fields be measured?

Back 82

 by seeing at what distance a person can perceive two separate points of touch

Front 83

what does two-point touch threshold measure?

Back 83

tactile acuity

Front 84

What is the lateral inhibition?

Back 84

Receptors where touch is the strongest are stimulated more than areas where touch is lighter

Front 85

Receptors that are most strongly stimulated _____those around them. What does this allow?

Back 85

inhibit, this allows us to perceive well-defined sensations at a single location instad of a "fuzzy" border

Front 86

Where does the lateral inhibition occur?

Back 86

in the Central Nervous System

Front 87

The ability to not notice the smell of fish from the previous day is due to tonic receptors.

 

true or false

Back 87

false,Sensory adaptation is due to phasic receptors that give a burst of firing when the stimulus starts and then again when it ends. See section 10.01 of the text for more information.

Front 88

Receptive fields that do not receive a strong stimulation will help sharpen the sensation by

Back 88

lateral inhibition

 

Those receptors that are on the edges of the stimulation will have their stimulation reduced which will strengthen the stimulus to those receptors that are more central, increasing their acuity. See section 10.02 of the text for more information.

Front 89

How many neurons are in the somatesthetic pathway from the skin to the postcentral gyrus?

Back 89

3, Sensory pathways will generally have three neurons. The first neuron runs from the receptor to the spinal cord. The second neuron runs through the spinal cord to the thalamus. The third neuron runs from the thalamus to the somatesthetic cortex on the postcentral gyrus. See section 10.02 of the text for further study.

Front 90

When a generator (receptor) potential reaches threshold, an action potential will be produced.

 

true or false

Back 90

true,

An action potential will be produced once the receptor potential has reached threshold. See section 10.01 of the text for more information.

Front 91

The greater the receptor density, the greater the sensory acuity.

 

true or false

Back 91

true

 

The more receptors present in a particular area, the better the sharpness (acuity) of the sensation. The finger tips have many more touch receptors than the upper arm, so more detailed touch information will be transmitted from the finger tips than from the upper arm. See section 10.02 of the text for more information.

Front 92

Sensations of heat, cold, and pain travel to the spinal cord, cross to the contralateral side, and ascend to the thalamus by way of the ______ tracts.

Back 92

lateral spinothalamic

 

Sensations of heat, cold, and pain travel to the spinal cord, cross to the contralateral side, and ascend to the thalamus by way of the lateral spinothalamic tracts. See section 10.02 of the text for more study on this topic.

Front 93

Match the stimulus example to the type of sensory receptor.
 

1.chemorceptor           touch

2.photoreceptor          carbon dioxide

3.mechanoreceptor   glow stick

4.nociceptor                  a burn

5. thermoreceptor       open oven

Back 93

1. carbon dioxide

2.glow stick

3. touch

4. a burn

5. an open oven

Front 94

When a stimulus is applied to a sensory ending, a graded response called a _______ potential is produced.

Back 94

generator