05a: Sensory Receptor Physiology

Question 1

Explain basic concept of “signal transduction”

Answer 1

Specialized nerve cell (receptor) absorbs particular kind of E and converts it to neural signal

Question 2

T/F: Each sensory receptor responds readily to only one form of E.

Answer 2

True

Question 3

The adequate stimulus for an olfactory receptor is:

Answer 3

odorant molecule

Question 4

T/F: The adequate stimulus is the only form of stimulus that a receptor will respond to.

Answer 4

False

Question 5

The sensation evoked in receptor is (the same/different) if different stimuli evoke the sensation.

Answer 5

The same

Question 6

List the three major categories of receptors (based on adequate stimulus).

Answer 6

1. Mechanoreceptors
2. Chemoreceptors
3. Radiant E receptors
4. Nociceptors

Question 7

Auditory and vestibular receptors are (mechano/chemo/radiant E) receptors.

Answer 7

Mechanoreceptors

Question 8

Olfactory receptors are (mechano/chemo/radiant E) receptors.

Answer 8

Chemoreceptors

Question 9

Gustatory receptors are (mechano/chemo/radiant E) receptors.

Answer 9

Chemoreceptors

Question 10

Proprioceptors are (mechano/chemo/radiant E) receptors.

Answer 10

Mechnoreceptors

Question 11

Light receptors are (mechano/chemo/radiant E) receptors.

Answer 11

Radiant E receptors

Question 12

Cold/warmth receptors are (mechano/chemo/radiant E) receptors.

Answer 12

Radiant E receptors

Question 13

The simplest receptors are those for (X), which terminate in tissues with which specialization of receptor endings?

Answer 13

X = pain/T

Free nerve endings

Question 14

Range fractionation refers to the phenomenon where as one receptor (X), another receptor (Y). This allows for impressive (Z) of many receptor systems.

Answer 14

X = reaches maximum frequency
Y = is just reaching threshold
Z = dynamic range

Question 15

The intensity of a stimulus is coded in which characteristic(s) of sensory system?

Answer 15

1. Frequency of firing of one sensory fiber AND

2. Number of activated fibers

Question 16

Slowly adapting receptor.

Answer 16

Tonic receptor

Question 17

Quickly adapting receptor.

Answer 17

Phasic receptor

Question 18

Pacinian corpuscles are (tonic/phasic) receptors.

Answer 18

Phasic

Question 19

In phasic receptors, firing frequency is proportional to:

Answer 19

Rate of change of stimulus

Question 20

Along with range fractionation, what’s the second mechanism used by receptor systems to (X).

Answer 20

X = broaden range of stimulus strength they can signal

Receptor adaption

Question 21

List the mechanisms responsible for adaptation of receptor potentials. Give example of each.

Answer 21

1. Accessory structures (pacinian corpuscle)

2. Level of secondary messengers (photoreceptors)

Question 22

Impulse Frequency proportional to (X) because both are also proportional to (Y).

Answer 22

X = stimulus intensity;
Y = generator potential amplitude

Question 23

The (X) in sensory receptor is analogous to EPSP of synapse.

Answer 23

X = receptor/generator potential

Question 24

List steps to sensory transduction.

Answer 24

1. Stimulus causes local change in permeability
2. Generator current
3. Local depolarization (generator potential)
4. Action potential
5. Adaptation