Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

W/Physiology > Topic 8.7 > Flashcards

Topic 8.7 Flashcards

1
Q

Where are grey and white matter in the SP?

A

White matter : superficial

Grey matter : inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is the organization of motor neurons in the grey matter?

A

Musculotopic organization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are somatic motor neurons?

A

Neurons that project to skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are autonomic motor neurons?

A

Neurons that project to smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

2 main lasses of somatic motor neurons

A

alpha and gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a motor unit?

A

motor neuron + all the sk muscle fibers it supplies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the main alpha motor neuron axon synapse with?

A

With extrafusal muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the size principle of motor innervation?

A

As more force is needed, a greater number of motor units are recruited, in an order according to the magnitude of their force output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which type of muscles have more / less alpha motor neuron innervation?

A

More : limb muscles

Less : muscles for manipulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do gamma motor neurons synapse with?

A

with intrafusal muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 3 types of inhibitory interneurons?

A
  • Ia
  • Ib
  • Renshaw cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the role of the Ia interneuron?

A

inhibitor of antagonist muscles in reflex arch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the role of the Ib interneuron?

A

Found in a reflex arch, where it is activated by a golgi tendon organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do Renshaw cells do?

A

They can modulate the strength of firing rate of a motor neuron via recurrent inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

3 examples of proprioceptive receptors

A
  • muscle spindle
  • gto
  • joint receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are muscle spindles especially abundant?

A

In muscles for fine movement (like extraocular muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

2 types of intrafusal fibers

A
  • nuclear chain fibre

- nuclear bag fibre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Sensory innervation of muscle spindles

A
  • Group Ia fibers (for both)

- Group II fibers (for nuclear chain fiber)

19
Q

What do sensory Ia fibers in muscle spindles?

A

Detect velocity of length change

20
Q

What do sensory II fibers in muscle spindles?

A

detect change of length of the muscle fiber

21
Q

Motor innervation of nuclear bag and nuclear chain fibre

A

Dynamic and static gamma motor neuron

22
Q

What does GTO sense?

A

Tension when we contract the muscles (stretch receptor)

23
Q

What type of afferent fibers innervate GTO?

A

type Ib afferent nerves

24
Q

What is a reflex?

A

an involuntary instantaneous response to an eliciting stimulus

25
Q

3 parts of the reflex arc?

A
  • afferent limb
  • central component
  • efferent limb
26
Q

4 reflexes

A
  • Stretch (myotatic) reflex
  • GT reflex (inverse myotatic)
  • Flexor withdrawal
  • Baby reflexes
27
Q

Types of synapses of group Ia afferent fibers (2)

A
  • monosynaptic

- bisynaptic

28
Q

What maneuver allows better testing of myotatic reflex?

A

Jendrassik maneuver

29
Q

What type of reflex is the GTO reflex?

A

polysynaptic reflex

30
Q

Which muscle is relaxed in the GTO reflex?

A

The agonist / homonymous muscle (by inhibitory interneuron)

31
Q

Which fiber types can carry the noxious stimulus?

A

Type III, IV fibers - a delta axons

32
Q

What is the stimulus of the flexor withdrawal reflex?

A

pain (noxious stimulus)

33
Q

What is the portion of the reflex that crosses to the other side of SP called?

A

crossed-extension reflex

34
Q

4 baby reflexes

A
  • positive support reflex
  • babinski reflex
  • palmar grasp reflex
  • labyrinthine head righting reflex
35
Q

What is babinski reflex?

A

big toe of baby’s foot moves upward after the sole is stroked

36
Q

What is a spinal cord transection?

A

a tear within the sp as a result of a traumatic injury

37
Q

2 types of sp cord transection syndromes

A
  • upper motor neuron syndrome

- lower motor neuron syndrome

38
Q

Symptoms of UMN (3)

A
  • muscle weakness
  • hyperreflexia
  • tight muscles (hypertonia)
39
Q

Symptoms of LMN (3)

A
  • weeakened reflexes
  • flaccid muscles (hypo / atonia)
  • muscle atrophy
40
Q

What is quadriplegia?

A

lesion at T1 or above

41
Q

When do we require mechanical ventilation?

A

if lesion above C4

42
Q

What is paraplegia?

A

Below the level of T1

43
Q

What is spinal shock?

A

loss of reflex, motor and sensory function below the level of a spinal cord injury

W/Physiology (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions