Lecture 5

Question 1

What is the purpose of receptors

Answer 1

they tell us about the external environment, our location in space, and whats going on inside our body

Question 2

What is proprioception

Answer 2

position of body parts

Question 3

What is exteroception

Answer 3

vision, hearing, smell, touch

Question 4

What is interoception

Answer 4

internal objects, organs

Question 5

Percieved sensation is __________ as it relates to stimulus intensity

Answer 5

logarithmic

Question 6

What side of the spinal cord do sensory neurons come in

Answer 6

dorsal

Question 7

What is the proprioceptor neuron composed of

Answer 7

body, long t-shaped axon, and sensory ending

Question 8

Where is the body of the proprioceptor neuron located

Answer 8

in spinal ganglia (dorsal root ganglia)

Question 9

What type of conduction to proprioceptor neurons do

Answer 9

antidromic

Question 10

What is the most complex/detailed type of sensory proprioceptor

Answer 10

muscle splindle

Question 11

Are muscle spindles parallel or perpendicular to extrafusal fibers

Answer 11

parallel

Question 12

What two types of sensory endings can be found in muscle spindles

Answer 12

primary (Ia)

secondary (II)

Question 13

Which intrafusal fibers are primary endings found in

Answer 13

all of them

Question 14

Secondary endings are not seen in ______

Answer 14

dynamic bag fibers

Question 15

What are the characteristics of the primary sensory endings

Answer 15

really big and fast

Question 16

How do the secondary sensory endings compare to the primary

Answer 16

they are half the size and speed of the primary

Question 17

What three components do muscle spindles contain

Answer 17

intrafusal muscle fibers
afferent sensory fiber endings
efferent motor fiber endings

Question 18

Gamma motor neurons, which are much smaller than alpha motor neurons, innervate what region of the intrafusal fibers

Answer 18

contractile polar

Question 19

When a gamma motor neuron activates an intrafusal fiber, it will contract, thus increasing its __________

Answer 19

sensitivity to stretch

Question 20

What are the three types of intrafusal fibers

Answer 20

dynamic bag fibers
static bag fibers
chain fibers

Question 21

Dynamic bag fibers are innervated by

Answer 21

single primary (Ia) sensory ending
dynamic gamma motor neuron

Question 22

Static bag fibers are innervated by

Answer 22

single primary (Ia) sensory ending
a secondary (II) ending
static gamma motor neuron

Question 23

Chain fibers are innervated by

Answer 23

single primary (Ia) sensory ending
a secondary (II) ending
static gamma motor neuron

Question 24

What are the primary (Ia) sensory endings sensitive to

Answer 24

muscle length and speed of lengthening

Question 25

What are the secondary (II) endings sensitvie to

Answer 25

length but not rate

Question 26

What do gamma motor neurons do

Answer 26

shorten spindles to increase sensitivity to changes in length

Question 27

What are the two types of small motoneurons (gamma) innervating intrafusal fibers of muscle spindles

Answer 27

dynamic and static

Question 28

While dynamic gamma motoneurons innervate dynamic bag fibers, what do static motoneurons innervate

Answer 28

static bag and chain fibers

Question 29

What are gamma motoneurons and what do they innervate

Answer 29

system to modify sensitivity of the spindle endings; innervate intrafusal fibers

Question 30

Where are golgi tendon organs located

Answer 30

at the muscular tendonous junction

Question 31

What are golgi tendon organs innervated with

Answer 31

innervated with fast-conducting (Ib) axons of sensory neurons in spinal ganglia (not gamma motor neurons)

Question 32

What are GTOs sensitive to

Answer 32

changes in force or tension

Question 33

GTOs are active during what type(s) of muscle actions

Answer 33

all three: concentric, eccentric, and isometric

Question 34

Muscle force and joint capsule tension have what type of relationship

Answer 34

direct; as one increases the other increases as well

Question 35

When muscle force and joint capsule tension increase, articular receptors ______ their response

Answer 35

increase

Question 36

What are articular receptors sensitive to

Answer 36

changes in joint angle and position

Question 37

What are cutaneous and subcutaneous receptors good for

Answer 37

touch (gripping and holding things)

Question 38

What receptor measures vertical pressure and are innervated by one axon

Answer 38

merkel disks

Question 39

Receptors that measure quickly changing pressure and each is innervated by greater than or equal to 2 axons

Answer 39

meissner corpuscles

Question 40

Receptors that measure deformation of large skin areas and are slowly adapting

Answer 40

ruffini endings

Question 41

Receptors that measure rapidly changing mechanical deformation such as vibration and are the deepest receptors

Answer 41

pacinian corpuscles

Question 42

Afferent nerves from what receptors go into the spinal cord through the dorsal roots

Answer 42

peripheral

Question 43

Where are articular receptors located

Answer 43

in the joint capsule ligament

Question 44

What are the two primary differences between muscle spindles and GTOs

Answer 44

muscle spindles: 2 sensory neurons, parallel, sensitive to length, gamma motor neuron system GTO: only have (Ib), in series, sensitive to force

Question 45

Proprioceptors induce changes in muscle activity that bypass ________

Answer 45

consciousness

Question 46

What tells us where our arms and legs are and how heavy or light, or rough or soft the objects we handle are

Answer 46

proprioceptors

Question 47

What kind of system do proprioceptors help to create that the brain uses to plan and execute movements

Answer 47

internal reference (nervous system memory)