Module 2 - Sensory receptors

Question 1

What are sensory receptors

Answer 1

specialized cells/ending of cells that convert stimulus energy to electrical potentials that can be interpreted by the NS. They work with afferent fibres

Question 2

What are the 4 types of sensory receptors and what do each do

Answer 2

1. Mechanoreceptors - convert mechanical energy (force)
2. Photoreceptors - convert light energy (photons)
3. Chemoreceptors - convert chemical energy (tastebuds)
4. Thermoreceptors - convert thermal energy

Question 3

What is a receptor potential

Answer 3

mechanism where the stimulus energy leads to a change in the electro-chemical state of the cell. I

Question 4

what’s common to all sensory receptors

Answer 4

they convert “passive” receptor potential to an action potential

Question 5

how is the receptor potential generated

Answer 5

by diffusion of ions in or out of the cell. ions passively diffuse along the cell

Question 6

What’s different in the Action potential than in the receptor potential

Answer 6

AP’s are constantly regenerated, RP’s aren’t.

Question 7

what is a modality

Answer 7

when you are experiencing something

Question 8

In what ways can a receptor represent certain types of stimuli

Answer 8

1. By type/modality
2. By onset,offset or duration
3. Intensity
4. Location

Question 9

What are the 8 different types of stimulus modalities

Answer 9

1. Touch/Tactioception
2. Movement/Proprioception
3. Orientation/Equilibioception
4. Hearing/Audioception
5. Sight/Opthalmoception
6. Smell/Olfacoception
7. Taste/Gustaocepton
8. Pain/Nocicepton

Question 10

What is Tactioception

Answer 10

Touch - sense of changes to external/internal body environment

Question 11

What is Proprioception

Answer 11

movement - sense of position/movement of body; force/effort of movement

Question 12

What is Equilibrioception

Answer 12

Orientation - sense of body position & movement in relation to gravity

Question 13

What is Audioception

Answer 13

Hearing - sense of sound waves from environment

Question 14

What is Opthalmoception

Answer 14

Sight - sense of objects/environment from visible light

Question 15

What is Olfacoception

Answer 15

Smell - sense of CHEMICAL odorants in nasal cavity

Question 16

What is Gustaoception

Answer 16

Taste - sense of substances that CHEMICALLY react in mouth

Question 17

What is Nociception

Answer 17

Pain - sense of pain related to injury/damage

Question 18

what 2 senses are chemical

Answer 18

1. Smell/Olfacoception
2. Taste/Gustaoception

Question 19

What are the 4 classes of receptors

Answer 19

1. somatosensory
2. vestibular
3. visual
4. auditory

Question 20

what are somatosensory receptors

Answer 20

any mechano,thermo, or nocireceptors in skin, fatty tissue under the skin, muscle or musculoskeletal tissue

Question 21

what are vestibular receptors

Answer 21

mechanoreceptors within the otoliths/labyrinths of the inner ear

Question 22

what are visual receptors

Answer 22

photoreceptors in the retina

Question 23

what are auditory receptors

Answer 23

mechanoreceptors in the cochlea within the inner ear

Question 24

describe fast-adapting receptors

Answer 24

• vigorous
• don’t last long
• stimulus energy is always changing

Question 25

describe slow-adapting receptors

Answer 25

- paced/maintain constant speed - last long time - stimulus energy is constant

Question 26

What is the "labeled lines" hypothesis

Answer 26

sensory information from different modalities are transmitted to the brain through separate dedicated pathways or "labeled lines."

Question 27

do signals remain together for the whole duration from when they are sensed until they're integrated by the NS?

Answer 27

axons bundle together but their signals remain separate until reaching higher areas of the NS

Question 28

what does somatotopic mean

Answer 28

preserved info about body location

Question 29

what does tonotopic mean

Answer 29

preserved info about sound frequency

Question 30

what does retinotopic mean

Answer 30

preserved info about spatial location in the visual field

Question 31

describe the path visible light takes in photoreceptors

Answer 31

1. pigment (e.g. Rhodopsin) absorbs light 2. Initiated a 2nd messenger pathway that closes Na+ ion channels 3. Less Na+ influx lowers amplitude of receptor potential 4. Less neurotransmitter is released when the receptor potential reaches the end of the receptor

Question 32

What is the intermediary cell called that influences the sensory nerve/ganglion cell

Answer 32

bipolar cell

Question 33

does the bipolar cell have a smaller or bigger influence when the receptor potential is small

Answer 33

stronger and vice versa

Question 34

Describe the rods in the eyes

Answer 34

1. located on boundary of retina 2. contain rhodopsin pigment 3. all rods have same type of rhosopsin --> detect cyan/green

Question 35

Describe the cones in the eyes

Answer 35

1. located on center of retina 2. contain iodopsin pigment 3. 3 different types, each has different form iodopsin to detect specific wavelength

Question 36

What type of receptors are hair cells and what do they do

Answer 36

mechanoreceptor. they mediate auditory & vestibular senses