Section 4

Question 1

Neural structures that detect information about the environment

Answer 1

Receptors

Question 2

What are the four main types of receptors?

Answer 2

1. Mechanoreceptors
2. Thermoreceptors
3. Nociceptors
4. Chemoreceptors

Question 3

What do mechanoreceptors respond to?

Answer 3

Structural distortion like:

1. Stretching
2. Skin distortion
3. Vibration
4. Hair movement
5. Pressure

Question 4

Where are mechanoreceptors located?

Answer 4

1. Skin (cutaneous)
2. Muscles (fleshy pt of m. spindle)
3. Tendons (GTO)
4. Ligaments (movement and position)

Question 5

What temperature ranges do thermoreceptors respond to?

Answer 5

1. Cold (15 - 30 degrees celsius)

2. Warm (30 - 42 degrees celsius)

Question 6

Where are thermoreceptors located?

Answer 6

In the skin as free nerve endings

Question 7

Receptors that respond to chemical mediators (as part of the inflammatory response), and other noxious stimuli (like tearing of tissue)

Answer 7

Nociceptors

Question 8

Needed for healing since vasculature heals injuries

Answer 8

Inflammatory response

Question 9

Where are nociceptors located?

Answer 9

1. Skin
2. Visceral organ walls
3. Skeletal muscles
4. Joint capsules
5. Outer layer of the annulus fibrosis (disk)
6. Periosteum of bone

Question 10

Receptor _______ means the receptor produce or generates an AP; travels from the receptor toward the spinal cord

Answer 10

Activation

Question 11

The ____________ causes receptor activation

Answer 11

Adequate stimulus

Question 12

The specific form of energy that the receptor responds most easily to; takes the least amount of this energy for the receptor to produce an AP

Answer 12

Adequate stimulus (think eye = light energy, but can be activated by mechanical energy)

Question 13

What is the adequate stimulus of mechanoreceptors?

Answer 13

Structural distortion and movement of the receptor

Question 14

Mechanoreceptors give rise to the sense of:

Answer 14

1. Proprioception (position)

2. Kinesthesia (movement)

Question 15

Name the 3 specific stimuli of mechanoreceptors.

Answer 15

1. Structural distortion like stretching
2. Vibration
3. Movement (hair follicle receptor)

Question 16

Specialized mechanoreceptors signal the CNS about the position and movement of body parts, these receptors are known as ________.

Answer 16

Proprioceptors

Question 17

Name the 3 types of proprioceptors.

Answer 17

1. Muscle spindle
2. Golgi Tendon Organ
3. Joint receptors

Question 18

What proprioceptor senses stretch?

Answer 18

Muscle spindles (primary afferent = rate of length change, senses it as it’s happening; secondary afferent = static length, long vs. short)

Question 19

What proprioceptor senses muscle contraction tension?

Answer 19

GTO

Question 20

What proprioceptor senses movement and pressure?

Answer 20

Joint receptors

Question 21

Where are joint receptors located?

Answer 21

Ligaments and joint capsule

Question 22

Term that refers to when a chemical causes a receptor to be more susceptible or responsive to future stimuli to fire AP; receptor becomes like a “hair-trigger”; not enough to fire AP

Answer 22

Sensitization

Question 23

The stimulus that causes the nociceptor to immediately produce and action potential which is transmitted through the afferent axon to the spinal cord

Answer 23

Activation

Question 24

The tendency for any nerve cell to fire an AP in response to future stimuli is known as ________

Answer 24

Sensitization of the neuron

Question 25

A motor neuron is activated when it produces an _________

Answer 25

Action potential

Question 26

Adaptation of a receptor means that during the application of the stimulus the receptor

Answer 26

gets used to the stimulus and turns-off (or more technically, stops firing APs)

Question 27

A rapidly adapting receptor is also known as a _____ receptor

Answer 27

Phasic

Question 28

A slowly adapting receptor is also known as a _____ receptor

Answer 28

Tonic

Question 29

A sensory axon with all its receptor endings

Answer 29

Sensory unit

Question 30

The region of skin innervated by the receptor endings is the sensory neuron’s ______________

Answer 30

Receptive or receptor field

Question 31

True or False:

Receptors are voltage-gated channels

Answer 31

False; they are NOT voltage-gated channels

Question 32

What are the stimulus energy types that are charged to electrical events in the receptor?

Answer 32

1. Mechanical
2. Electrical
3. Chemical

Question 33

Change of stimulus energy to electrical event is defined as ___________.

Answer 33

Sensory transduction

Question 34

_______ potentials are proportional to the strength of the stimulus energy.

Answer 34

Generator or Receptor

Question 35

If generator potentials sum or are great enough, they trigger ______ in the afferent axon

Answer 35

APs

Question 36

In a rapidly adapting receptor, the receptor ________ while the stimulus remains

Answer 36

Turns off fast

Question 37

In a slow adapting receptor the frequency (decreases/ increases) as receptor response decreases

Answer 37

Decreases

Question 38

In a slow adapting receptor, the receptor _______ and the response decreases for the entire stimulus

Answer 38

Stays on

Question 39

What substances cause activation in afferent fibers of nociceptors?

Answer 39

1. Bradykinin
2. Serotonin
3. Potassium
4. Histamine

Question 40

What substances cause sensitization in afferent fibers of nociceptors?

Answer 40

1. Prostoglandins
2. Leukotrienes
3. Hydrogen ions
4. Substance P
5. Hypoxia

Question 41

Where are receptor fields located?

Answer 41

Skin or internal organ

Question 42

A greater stimulus gives you a ______ graded potential, which results in a _______ frequency of action potential

Answer 42

Greater; higher

Question 43

Frequency of action potentials are (inversely/directly) proportional to the amplitude of stimulus in CNS.

Answer 43

Directly